Terminal apparatus, base station apparatus, and communication method

ABSTRACT

A terminal apparatus includes: a receiver configured to receive a DCI format and a PDSCH scheduled by the DCI format; and a transmitter configured to transmit HARQ-ACK information. A first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format. The HARQ-ACK information is generated based at least on a T-DAI for a second PDSCH group different from the first PDSCH group. A bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of the number of serving cells configured.

TECHNICAL FIELD

The present invention relates to a terminal apparatus, a base station apparatus, and a communication method.

This application claims priority to JP 2019-179565 filed on 30 Sep. 2019, the contents of which are incorporated herein by reference.

BACKGROUND ART

In the 3^(rd) Generation Partnership Project (3GPP), a radio access method and a radio network for cellular mobile communications (hereinafter referred to as “Long Term Evolution (LTE)” or “Evolved Universal Terrestrial Radio Access (EUTRA)”) have been studied. In LTE, a base station apparatus is also referred to as an evolved NodeB (eNodeB), and a terminal apparatus is also referred to as User Equipment (UE). LTE is a cellular communication system in which multiple areas covered by a base station apparatus are distributed in a cell structure. A single base station apparatus may manage multiple serving cells.

3GPP has been studying a next generation standard (New Radio or NR) (NPL 1) to make a proposal for International Mobile Telecommunication (IMT)-2020, a standard for a next generation mobile communication system developed by the International Telecommunication Union (ITU). NR is required to satisfy requirements for three scenarios including enhanced Mobile BroadBand (eMBB), massive Machine Type Communication (mMTC), and Ultra Reliable and Low Latency Communication (URLLC) in a single technology framework.

CITATION LIST Non Patent Literature

NPL 1: “New SID proposal: Study on New Radio Access Technology”, RP-160671, NTT docomo, 3GPP TSG RAN Meeting #71, Goteborg, Sweden, 7th to 10 Mar. 2016.

SUMMARY OF INVENTION Technical Problem

One aspect of the present invention provides a terminal apparatus that efficiently performs communication, a communication method used for the terminal apparatus, a base station apparatus that efficiently performs communication, and a communication method used for the base station apparatus.

Solution to Problem

(1) The first aspect of the present invention is a terminal apparatus including: a receiver configured to receive a Downlink Control Information (DCI) format and a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI format; and a transmitter configured to transmit HARQ-ACK information, wherein a first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format, the HARQ-ACK information is generated based at least on a Total Downlink Assignment Index (T-DAI) for a second PDSCH group different from the first PDSCH group, and a bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of the number of serving cells configured.

(2) The second aspect of the present invention is a base station apparatus including: a transmitter configured to transmit a Downlink Control Information (DCI) format and a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI format; and a receiver configured to receive HARQ-ACK information, wherein a first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format, the HARQ-ACK information is generated based at least on a Total Downlink Assignment Index (T-DAI) for a second PDSCH group different from the first PDSCH group, and a bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of the number of serving cells configured.

(3) The third aspect of the present invention is a communication method for a terminal apparatus, the communication method including the steps of: receiving a Downlink Control Information (DCI) format and a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI format; and transmitting HARQ-ACK information, wherein a first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format, the HARQ-ACK information is generated based at least on a Total Downlink Assignment Index (T-DAI) for a second PDSCH group different from the first PDSCH group, and a bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of the number of serving cells configured.

(4) The fourth aspect of the present invention is a communication method for a base station apparatus, the communication method including the steps of: transmitting a Downlink Control Information (DCI) format and a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI format; and receiving HARQ-ACK information, wherein a first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format, the HARQ-ACK information is generated based at least on a Total Downlink Assignment Index (T-DAI) for a second PDSCH group different from the first PDSCH group, and a bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of the number of serving cells configured.

Advantageous Effects of Invention

According to the present invention, the terminal apparatus can efficiently perform communication. The base station apparatus can efficiently perform communication.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a conceptual diagram of a radio communication system according to an aspect of the present embodiment.

FIG. 2 is an example illustrating a relationship of N^(slot) _(symbol), a subcarrier spacing configuration μ, a slot configuration, and a CP configuration according to an aspect of the present embodiment.

FIG. 3 is a schematic diagram illustrating an example of a resource grid in a subframe according to an aspect of the present embodiment.

FIG. 4 is a diagram illustrating an example of monitoring occasions for search space sets according to an aspect of the present embodiment.

FIG. 5 is a schematic block diagram illustrating a configuration of a terminal apparatus 1 according to an aspect of the present embodiment.

FIG. 6 is a schematic block diagram illustrating a configuration of a base station apparatus 3 according to an aspect of the present embodiment.

FIG. 7 is a diagram illustrating a correspondence example between the monitoring occasion for the search space set (Monitoring occasion for search space set) and the monitoring occasion for a PDCCH (Monitoring occasion for PDCCH) according to an aspect of the present embodiment.

FIG. 8 is a diagram illustrating a configuration example of a set of monitoring occasions for the PDCCH for a slot n according to an aspect of the present embodiment.

FIG. 9 is a diagram illustrating a configuration example of a set of monitoring occasions for the PDCCH for a slot n according to an aspect of the present embodiment.

FIG. 10 is a diagram illustrating a configuration example of a set of monitoring occasions for the PDCCH for a slot n according to an aspect of the present embodiment.

FIG. 11 is a diagram illustrating an example related to indication of a counter DAI and a total DAI according to an aspect of the present embodiment.

FIG. 12 is a diagram illustrating an example of a procedure of configuration of a HARQ-ACK codebook according to an aspect of the present embodiment.

FIG. 13 is a diagram illustrating an example of a procedure of configuration of a HARQ-ACK codebook according to an aspect of the present embodiment.

FIG. 14 is a diagram illustrating an example of a procedure of configuration of a HARQ-ACK codebook according to an aspect of the present embodiment.

FIG. 15 is a diagram illustrating a method of indicating the total DAI by a DCI payload according to an aspect of the present embodiment.

FIG. 16 is a diagram illustrating an example of switching of the DCI field used for indication of the total DAI according to an aspect of the present embodiment.

DESCRIPTION OF EMBODIMENTS

An embodiment of the present invention will be described below.

“A and/or B” may be a term including “A”, “B”, or “A and B”.

ceil(A) is a roof function for A. ceil(A) may be a function that outputs a minimum integer within a range of not falling below A. log 2(B) is a logarithm function for calculating a logarithm of B to base 2. pow(A, B) is a power function defined for a constant A. In other words, pow(A, B) is A to the power of B.

The fact that a parameter or information indicates one or multiple values may mean that the parameter or the information includes at least a parameter or information indicating the one or the multiple values. A higher layer parameter may be a single higher layer parameter. The higher layer parameter may be an Information Element (IE) including multiple parameters.

FIG. 1 is a conceptual diagram of a radio communication system according to an aspect of the present embodiment. In FIG. 1 , the radio communication system includes terminal apparatuses 1A to 1C and a base station apparatus 3. Hereinafter, each of the terminal apparatuses 1A to 1C is also referred to as a terminal apparatus 1.

The base station apparatus 3 may include one of or both a Master Cell Group (MCG) and a Secondary Cell Group (SCG). The MCG is a group of serving cells at least including a Primary Cell (PCell). The SCG is a group of serving cells including at least a Primary Secondary Cell (PSCell). The PCell may be a serving cell that is given based on initial connection. The MCG may include one or multiple Secondary Cells (SCells). The SCG may include one or multiple SCells. A serving cell identity is a short identity for identifying the serving cell. The serving cell identity may be provided by a higher layer parameter.

In the following, frame configuration will be described.

In the radio communication system according to an aspect of the present embodiment, Orthogonal Frequency Division Multiplex (OFDM) is at least used. An OFDM symbol is a unit of OFDM in the time domain. The OFDM symbol at least includes one or multiple subcarriers. The OFDM symbol may be converted into a time-continuous signal in baseband signal generation.

A SubCarrier Spacing (SCS) may be provided by a subcarrier spacing Δf=2^(μ)·15 kHz. For example, a subcarrier spacing configuration μ may be configured to be any of 0, 1, 2, 3, 4, and/or 5. For a certain BandWidth Part (BWP), the subcarrier spacing configuration μ may be provided by a higher layer parameter.

In the radio communication system according to an aspect of the present embodiment, a time unit T_(c) is used for representing a length of the time domain. The time unit T_(c) may be given by T_(c)=1/(Δf_(max)·N_(f)). Δf_(max) may be the maximum value of the subcarrier spacing supported by the radio communication system according to an aspect of the present embodiment. Δf_(max) may be Δf_(max)=480 kHz. N_(f) may be N_(f)=4096. A constant κ is κ=Δf_(max)·N_(f)/(Δf_(ref)N_(f, ref))=64. Δf_(ref) may be 15 kHz. N_(f, ref) may be 2048.

The constant κ may be a value indicating a relationship between a reference subcarrier spacing and T_(c). The constant κ may be used for the length of a subframe. Based at least on the constant κ, the number of slots included in the subframe may be given. Δf_(ref) is the reference subcarrier spacing, and N_(f, ref) is a value corresponding to the reference subcarrier spacing.

Downlink transmission and/or uplink transmission includes frames of 10 ms. The frame includes 10 subframes. The length of the subframe is 1 ms. The length of the frame may be provided regardless of the subcarrier spacing Δf. In other words, the frame configuration may be provided regardless of μ. The length of the subframe may be provided regardless of the subcarrier spacing Δf. In other words, the configuration of the subframe may be provided regardless of μ.

For a certain subcarrier spacing configuration μ, the number and indexes of slots included in a subframe may be provided. For example, a first slot number n^(μ) _(s) may be provided in ascending order ranging from 0 to N^(subframe, μ) _(slot)−1 within a subframe. For the subcarrier spacing configuration μ, the number and indexes of slots included in a frame may be provided. For example, a second slot number n^(μ) _(s, f) may be provided in ascending order ranging from 0 to N^(frame, μ) _(slot)−1 within a frame. N^(slot) _(symb) continuous OFDM symbols may be included in one slot. N^(slot) _(symb) may be provided based at least on a part or an entirety of a slot configuration and/or a Cyclic Prefix (CP) configuration. The slot configuration may be provided at least by a higher layer parameter tdd-UL-DL-ConfigurationCommon. The CP configuration may be provided based at least on a higher layer parameter. The CP configuration may be given based at least on dedicated RRC signaling. Each of the first slot number and the second slot number is also referred to as slot number (slot index).

FIG. 2 is an example illustrating a relationship of N^(slot) _(symb), a subcarrier spacing configuration μ, and a CP configuration according to an aspect of the present embodiment. In FIG. 2A, for example, the subcarrier spacing configuration is two, and the CP configuration is a normal cyclic prefix (normal CP), N^(slot) _(symb)=14, N^(frame, μ) _(slot)=40, and N^(subframe, μ) _(slot)=4. In FIG. 2B, for example, the subcarrier spacing configuration μ is two, and the CP configuration is an extended cyclic prefix (extended CP), N^(slot) _(symb)=12, N^(frame, μ) _(slot)=40, and N^(subframe, μ) _(slot)=4.

Physical resources will be described below.

An antenna port is defined in a manner in which a channel through which a symbol is transmitted in one antenna port can be estimated from a channel through which another symbol is transmitted in the same antenna port. In a case that a large scale property of a channel through which a symbol is transmitted at one antenna port can be estimated from a channel through which a symbol is transmitted at another antenna port, the two antenna ports are referred to as Quasi Co-Located (QCL). The large scale property may at least include long term performance of a channel. The large scale property may at least include a part or all of delay spread, Doppler spread, Doppler shift, an average gain, an average delay, and a beam parameter (spatial Rx parameters). The fact that the first antenna port and the second antenna port are QCL with respect to a beam parameter may mean that a receive beam assumed by a receiver for the first antenna port and a receive beam assumed by the receiver for the second antenna port are the same. The fact that the first antenna port and the second antenna port are QCL with respect to a beam parameter may mean that a transmit beam assumed by a receiver for the first antenna port and a transmit beam assumed by the receiver for the second antenna port are the same. In a case that the large scale property of a channel through which a symbol is transmitted in one antenna port can be estimated from a channel through which a symbol is transmitted in another antenna port, the terminal apparatus 1 may assume that the two antenna ports are QCL. The fact that two antenna ports are QCL may mean that it is assumed that the two antenna ports are QCL.

For each set of a subcarrier spacing configuration and a carrier, a resource grid including N^(μ) _(RB, x)N^(RB) _(sc) subcarriers and N^((μ)) _(symb)N^(subframe, μ) _(symb) OFDM symbols is provided. N^(μ) _(RB, x) may indicate the number of resource blocks provided for the subcarrier spacing configuration μ for a carrier x. N^(μ) _(RB, x) may indicate the maximum number of resource blocks provided for the subcarrier spacing configuration μ for the carrier x. The carrier x indicates either a downlink carrier or an uplink carrier. In other words, x is “DL” or “UL”. N^(μ) _(RB) is a name including N^(μ) _(RB, DL) and/or N^(μ) _(RB, UL). N^(RB) _(sc) may indicate the number of subcarriers included in one resource block. At least one resource grid may be provided for each antenna port p and/or for each subcarrier spacing configuration μ and/or for each Transmission direction configuration. The transmission direction at least includes a DownLink (DL) and an UpLink (UL). Hereinafter, a set of parameters including at least some or all of the antenna port p, the subcarrier spacing configuration μ, and the transmission direction configuration is also referred to as a first radio parameter set. In other words, one resource grid may be provided for each first radio parameter set.

In the downlink, a carrier included in a serving cell is referred to as a downlink carrier (or a downlink component carrier). In the uplink, a carrier included in a serving cell is referred to as an uplink carrier (uplink component carrier). A downlink component carrier and an uplink component carrier are collectively referred to as a component carrier (or a carrier).

Each element in the resource grid provided for each first radio parameter set is referred to as a resource element. The resource element is identified by an index k_(sc) in the frequency domain and an index l_(sym) in the time domain. For a certain first radio parameter set, the resource element is identified by the index k_(sc) in the frequency domain and the index l_(sym) in the time domain. The resource element to be identified by the index k_(sc) of the frequency domain and the index l_(sym) of the time domain is also referred to as a resource element (k_(sc), l_(sym)). The index k_(sc) of the frequency domain indicates any value from 0 to N^(μ) _(RB)N^(RB) _(sc)−1. N_(RB) may be the number of resource blocks provided for the subcarrier spacing configuration μ. N^(μ) _(RB) is the number of subcarriers included in the resource block, and N^(RB) _(sc)=12. The index k_(sc) in the frequency domain may correspond to the subcarrier index k_(sc). The index l_(sym) in the time domain may correspond to the OFDM symbol index l_(sym).

FIG. 3 is a schematic diagram illustrating an example of the resource grid in the subframe according to an aspect of the present embodiment. In the resource grid of FIG. 3 , the horizontal axis is the index l_(sym) in the time domain, and the vertical axis is the index k_(sc) in the frequency domain. In one subframe, the frequency domain of the resource grid includes N^(μ) _(RB)N^(RB) _(sc) subcarriers. In one subframe, the time domain of the resource grid may include 14·2^(μ) OFDM symbols. One resource block includes N^(RB) _(sc) subcarriers. The time domain of the resource block may correspond to 1 OFDM symbol. The time domain of the resource block may correspond to 14 OFDM symbols. The time domain of the resource block may correspond to one or multiple slots. The time domain of the resource block may correspond to one subframe.

For the terminal apparatus 1, performing transmission and/or reception by using only a subset of resource grids may be indicated. The subset of resource grids is also referred to as a BWP, and the BWP may be provided based at least on a part or an entirety of the higher layer parameter and/or DCI. The BWP is also referred to as a bandwidth part (BP). In other words, the terminal apparatus 1 may not receive an indication of transmission and/or reception using all sets of resource grids. In other words, the terminal apparatus 1 may receive an indication of transmission and/or reception using some frequency resources within the resource grid. One BWP may include multiple resource blocks in the frequency domain. One BWP may include multiple contiguous resource blocks in the frequency domain. A BWP configured for a downlink carrier is also referred to as a downlink BWP. A BWP configured for an uplink carrier is also referred to as an uplink BWP.

One or multiple downlink BWPs may be configured for the terminal apparatus 1. The terminal apparatus 1 may attempt to receive a physical channel (for example, a PDCCH, a PDSCH, and/or an SS/PBCH) in one downlink BWP out of the one or multiple downlink BWPs. The one downlink BWP is also referred to as an active downlink BWP.

One or multiple uplink BWPs may be configured for the terminal apparatus 1. The terminal apparatus 1 may attempt to transmit a physical channel (for example, a PUCCH, a PUSCH, and/or a PRACH) in one uplink BWP out of the one or multiple uplink BWPs. The one uplink BWP is also referred to as an active uplink BWP.

A set of downlink BWPs may be configured for each serving cell. The set of downlink BWPs may include one or multiple downlink BWPs. A set of uplink BWPs may be configured for each serving cell. The set of uplink BWPs may include one or multiple uplink BWPs.

A higher layer parameter is a parameter included in a higher layer signaling. The higher layer signaling may be a Radio Resource Control (RRC) signaling, or may be a Medium Access Control Control Element (MAC CE). Here, the higher layer signaling may be a signal of an RRC layer, or may be a signal of an MAC layer.

The higher layer signaling may be common RRC signaling. The common RRC signaling may at least include a part or all of the following feature C1 to feature C3.

-   Feature C1) Being mapped to a BCCH logical channel or a CCCH logical     channel -   Feature C2) Including at least a radioResourceConfigCommon     information element -   Feature C3) Being mapped to a PBCH

The radioResourceConfigCommon information element may include information indicating a configuration commonly used in a serving cell. The configuration used in a serving cell in common may at least include configuration of the PRACH. The configuration of the PRACH may at least indicate one or multiple random access preamble indexes. The configuration of the PRACH may at least indicate time/frequency resources of the PRACH.

The higher layer signaling may be dedicated RRC signaling. The dedicated RRC signaling may at least include a part or all of the following features D1 to D2.

-   Feature D1) Being mapped to a DCCH logical channel -   Feature D2) Including at least a radioResourceConfigDedicated     information element

The radioResourceConfigDedicated information element may include at least information indicating a configuration specific to the terminal apparatus 1. The radioResourceConfigDedicated information element may include at least information indicating a BWP configuration. The BWP configuration may indicate at least a frequency resource of the BWP.

For example, a MIB, first system information, and second system information may be included in the common RRC signaling. In addition, a higher layer message that is mapped to the DCCH logical channel and includes at least radioResourceConfigCommon may be included in the common RRC signaling. In addition, a higher layer message that is mapped to the DCCH logical channel and does not include the radioResourceConfigCommon information element may be included in the dedicated RRC signaling. In addition, a higher layer message that is mapped to the DCCH logical channel and includes at least the radioResourceConfigDedicated information element may be included in the dedicated RRC signaling.

The first system information may indicate at least a time index of a Synchronization Signal (SS) block. The SS block is also referred to as an SS/PBCH block. The SS/PBCH block is also referred to as an SS/PBCH. The first system information may include at least information related to a PRACH resource. The first system information may include at least information related to a configuration of initial connection. The second system information may be system information other than the first system information.

The radioResourceConfigDedicated information element may include at least information related to a PRACH resource. The radioResourceConfigDedicated information element may include at least information related to the configuration of initial connection.

In the following, physical channels and physical signals according to various aspects of the present embodiment will be described.

The uplink physical channel may correspond to a set of resource elements for carrying information that is generated in a higher layer. The uplink physical channel is a physical channel that is used in the uplink carrier. In the radio communication system according to an aspect of the present embodiment, at least a part or all of the following uplink physical channels are used.

-   -   Physical Uplink Control CHannel (PUCCH)     -   Physical Uplink Shared CHannel (PUSCH)     -   Physical Random Access CHannel (PRACH)

The PUCCH may be used to transmit Uplink Control Information (UCI). The uplink control information includes some or all of Channel State Information (CSI), a Scheduling Request (SR), and a Hybrid Automatic Repeat request ACKnowledgement (HARQ-ACK) corresponding to a transport block (TB, a Medium Access Control Protocol Data Unit (MAC PDU), Downlink-Shared Channel (DL-SCH), and/or a Physical Downlink Shared Channel (PDSCH)).

The HARQ-ACK information may include at least an HARQ-ACK bit corresponding at least to one transport block. The HARQ-ACK bit may indicate an acknowledgement (ACK) or a negative-acknowledgement (NACK) corresponding to one or multiple transport blocks. The HARQ-ACK information may include at least an HARQ-ACK codebook including one or multiple HARQ-ACK bits. The fact that the HARQ-ACK bit corresponds to one or multiple transport blocks may mean that the HARQ-ACK bit corresponds to a PDSCH including the one or the multiple transport blocks. The HARQ-ACK bit may indicate an ACK or NACK corresponding to one Code Block Group (CBG) included in the transport block.

The Scheduling Request (SR) may be used at least for requesting a resource of a PUSCH for initial transmission. A scheduling request bit may be used to indicate either a positive SR or a negative SR. The scheduling request bit indicating the positive SR is also referred to as “the positive SR being transmitted”. The positive SR may indicate that resources of the PUSCH for initial transmission are requested by the terminal apparatus 1. The positive SR may indicate that a scheduling request is triggered by the higher layer. The positive SR may be transmitted in a case that the higher layer indicates transmission of the scheduling request. The scheduling request bit indicating the negative SR is also referred to as “the negative SR being transmitted”. The negative SR may indicate that resources of the PUSCH for initial transmission are not requested by the terminal apparatus 1. The negative SR may indicate that the scheduling request is not triggered by the higher layer. The negative SR may be transmitted in a case that transmission of a scheduling request is not indicated by the higher layer.

Channel state information may include at least some or all of a Channel Quality Indicator (CQI), a Precoder Matrix Indicator (PMI), and a Rank Indicator (RI). The CQI is an indicator related to quality of a channel (for example, propagation intensity), and the PMI is an indicator indicating a precoder. The RI is an indicator indicating a transmission rank (or the number of transmission layers).

The PUCCH supports PUCCH formats (PUCCH formats 0 to 4). The PUCCH formats may be mapped to the PUCCH and may then be transmitted. The PUCCH format may be transmitted on the PUCCH. The fact that the PUCCH format is transmitted may mean that the PUCCH is transmitted.

The PUSCH may be used at least to transmit a transport block ((TB), the MAC PDU, a UL-SCH, and/or the PUSCH). The PUSCH may be used to transmit at least some or all of the transport block, the HARQ-ACK information, the channel state information, and the scheduling request. The PUSCH is used at least to transmit a random access message 3.

The PRACH is used at least to transmit a random access preamble (random access message 1). The PRACH may be used at least to indicate some or all of an initial connection establishment procedure, a handover procedure, a connection re-establishment procedure, synchronization for PUSCH transmission (timing adjustment), and a resource request for the PUSCH. The random access preamble may be used for notifying an index (random access preamble index) that is given by a higher layer of the terminal apparatus 1 to the base station apparatus 3.

In FIG. 1 , in uplink radio communication, the following uplink physical signals are used. The uplink physical signals need not be used for transmitting information output from a higher layer, but are used by a physical layer.

-   -   UpLink Demodulation Reference Signal (UL DMRS)     -   Sounding Reference Signal (SRS)     -   UpLink Phase Tracking Reference Signal (UL PTRS)

The UL DMRS is related to transmission of the PUSCH and/or the PUCCH. The UL DMRS is multiplexed on the PUSCH or the PUCCH. The base station apparatus 3 may use the UL DMRS for performing channel compensation of the PUSCH or the PUCCH. In the following, concurrent transmission of the PUSCH and the UL DMRS related to the PUSCH is simply referred to as transmission of the PUSCH. In the following, concurrent transmission of the PUCCH and the UL DMRS related to the PUCCH is simply referred to as transmission of the PUCCH. The UL DMRS related to the PUSCH is also referred to as the UL DMRS for the PUSCH. The UL DMRS related to the PUCCH is also referred to as the UL DMRS for the PUCCH.

The SRS need not be related to transmission of the PUSCH or the PUCCH. The base station apparatus 3 may use the SRS for measurement of a channel state. The SRS may be transmitted at the end of a subframe in an uplink slot or in a certain number of OFDM symbols from the end.

The UL PTRS may be a reference signal that is at least used for phase tracking. The UL PTRS may be related to a UL DMRS group at least including an antenna port used for one or multiple UL DMRSs. The fact that the UL PTRS and the UL DMRS group are related to each other may mean that an antenna port of the UL PTRS and a part or all of antenna ports included in the UL DMRS group are at least QCL. The UL DMRS group may be identified based at least on an antenna port having the smallest index in the UL DMRSs included in the UL DMRS group. The UL PTRS may be mapped to an antenna port having the smallest index in one or multiple antenna ports to which one codeword is mapped. The UL PTRS may be mapped to the first layer in a case that one codeword is at least mapped to the first layer and the second layer. The UL PTRS need not be mapped to the second layer. The index of the antenna port to which the UL PTRS is mapped may be given based at least on downlink control information.

In FIG. 1 , in downlink radio communication from the base station apparatus 3 to the terminal apparatus 1, the following downlink physical channels are used. The downlink physical channels are used by a physical layer for transmitting information output from a higher layer.

-   -   Physical Broadcast Channel (PBCH)     -   Physical Downlink Control Channel (PDCCH)     -   Physical Downlink Shared Channel (PDSCH)

The PBCH is used at least to transmit a Master Information Block ((MIB), and/or a Broadcast Channel (BCH)). The PBCH may be transmitted based on a prescribed transmission interval. The PBCH may be transmitted at an interval of 80 ms. The PBCH may be transmitted at intervals of 160 ms. Contents of information included in the PBCH may be updated at every 80 ms. A part or an entirety of the information included in the PBCH may be updated at every 160 ms. The PBCH may include 288 subcarriers. The PBCH may include 2, 3, or 4 OFDM symbols. The MIB may include information associated with an identifier (index) of a synchronization signal. The MIB may include information indicating at least a part of a number of the slot, a number of a subframe, and/or a number of a radio frame in which the PBCH is transmitted.

The PDCCH is used at least to transmit Downlink Control Information (DCI). The PDCCH may be transmitted with at least the downlink control information included therein. The PDCCH may include the downlink control information. The downlink control information is also referred to as a DCI format. The downlink control information may include at least either a downlink grant or an uplink grant. The DCI format used for scheduling the PDSCH is also referred to as a downlink DCI format. The DCI format used for scheduling the PUSCH is also referred to as an uplink DCI format. The downlink grant is also referred to as downlink assignment or downlink allocation. The uplink DCI format at least includes one or both of DCI format 0_0 and DCI format 0_1.

DCI format 0_0 includes at least some or all of 1A to 1E.

-   1A) DCI format identification field (Identifier for DCI formats     field) -   1B) Frequency domain resource allocation field (Frequency domain     resource assignment field) -   1C) Time domain resource allocation field (Time domain resource     assignment field) -   1D) Frequency hopping flag field -   1E) Modulation and Coding Scheme field (MCS field)

The DCI format identification field may be used at least to indicate which of one or multiple DCI formats the DCI format including the DCI format identification field corresponds to. The one or multiple DCI formats may be given based at least on a part or all of DCI format 1_0, DCI format 1_1, DCI format 0_0, and/or DCI format 0_1.

The frequency domain resource assignment field may be used at least to indicate assignment of a frequency resource for the PUSCH scheduled by the DCI format including the frequency domain resource assignment field. The frequency domain resource assignment field is also referred to as Frequency Domain Resource Allocation (FDRA) field.

The time domain resource assignment field may be used at least to indicate assignment of a time resource for the PUSCH scheduled by the DCI format including the time domain resource assignment field.

The frequency hopping flag field may be used at least to indicate whether frequency hopping is to be applied to the PUSCH scheduled by the DCI format including the frequency hopping flag field.

The MCS field may be used at least to indicate some or all of a modulation scheme for the PUSCH scheduled by the DCI format including the MCS field and/or a target coding rate. The target coding rate may be a target coding rate for a transport block of the PUSCH. The size of the transport block (Transport Block Size (TBS)) may be provided based at least on the target coding rate.

DCI format 0_1 includes at least some or all of 2A to 2I.

-   2A) DCI format identification field -   2B) Frequency domain resource allocation field -   2C) Time domain resource allocation field -   2D) Frequency hopping flag field -   2E) MCS field -   2F) CSI request field -   2G) BWP field -   2H) First UL DAI field (1^(st) downlink assignment index) -   2I) Second UL DAI field (2^(nd) downlink assignment index)

The first UL DAI field is used at least for indicating a transmission state of the PDSCH. In a case that a Dynamic HARQ-ACK codebook is used, the size of the first UL DAI field may be 2 bits.

The second UL DAI field is used at least for indicating a transmission state of the PDSCH. In a case that the dynamic HARQ-ACK codebook including two sub-codebooks is used, the size of the second UL DAI field may be 2 bits.

The BWP field may be used for indicating an uplink BWP to which the PUSCH that is scheduled by DCI format 0_1 is mapped.

The CSI request field is at least used for indicating the report of the CSI. The size of the CSI request field may be given based at least on a higher layer parameter ReportTriggerSize.

The downlink DCI format at least includes one or both of DCI format 1_0 and DCI format 1_1.

DCI format 1_0 includes at least some or all of 3A to 3M.

-   3A) DCI format identification field (Identifier for DCI formats     field) -   3B) Frequency domain resource allocation field (Frequency domain     resource assignment field) -   3C) Time domain resource allocation field (Time domain resource     assignment field) -   3D) Frequency hopping flag field -   3E) Modulation and Coding Scheme field (MCS field) -   3F) First CSI request field -   3G) PDSCH-to-HARQ feedback timing indicator field -   3H) PUCCH resource indication field (PUCCH resource indicator field) -   3I) First PGI field (first PDSCH Group Indicator field) -   3J) First NFI field (first New Feedback Indicator field) -   3K) First RPGI field (first Requested PDSCH Group Indicator field) -   3L) First DAI field (first Downlink Assignment Index field) -   3M) First other group DAI field (first Other Group Downlink     Assignment Index field)

The timing indication field from the PDSCH to the HARQ feedback may be a field indicating a timing K1. In a case that the index of the slot including the last OFDM symbol of the PDSCH is a slot n, the index of the slot including the PUCCH or the PUSCH including at least HARQ-ACK information corresponding to the transport block included in the PDSCH may be n+K1. In a case that the index of the slot including the last OFDM symbol of the PDSCH is a slot n, the index of the slot including the OFDM symbol at the head of the PUCCH or the OFDM symbol at the head of the PUSCH including at least HARQ-ACK information corresponding to the transport block included in the PDSCH may be n+K1.

The PDSCH-to-HARQ feedback timing indicator field (PDSCH-to-HARQ_feedback timing indicator field) may be hereinafter referred to as an HARQ indicator field.

The PUCCH resource indicator field may be a field indicating indexes of one or multiple PUCCH resources included in the PUCCH resource set.

Details of the first PGI field, the first NFI field, the first RPGI field, the first DAI field, and the first other group DAI field will be described later.

DCI format 1_1 includes at least some or all of 4A to 4O.

-   4A) DCI format identification field (Identifier for DCI formats     field) -   4B) Frequency domain resource allocation field (Frequency domain     resource assignment field) -   4C) Time domain resource allocation field (Time domain resource     assignment field) -   4D) Frequency hopping flag field -   4E) Modulation and Coding Scheme field (MCS field) -   4F) First CSI request field -   4G) PDSCH-to-HARQ feedback timing indicator field -   4H) PUCCH resource indication field (PUCCH resource indicator field) -   4J) BWP field -   4K) Second PGI field (second PDSCH Group Indicator field) -   4L) Second NFI field (second New Feedback Indicator field) -   4M) Second RPGI field (second Requested PDSCH Group Indicator field) -   4N) Second DAI field (second Downlink Assignment Index field) -   4O) Second other group DAI field (first Other Group Downlink     Assignment Index field)

The BWP field may be used to indicate the downlink BWP to which the PDSCH scheduled by DCI format 1_1 is mapped.

Description of the second PGI field, the second NFI field, the second RPGI field, the second DAI field, and the second other group DAI field will be given later.

DCI format 2_0 may at least include one or multiple Slot Format Indicators (SFIs).

Each DCI format (DCI format 1_0, DCI format 1_1, DCI format 0_0, and/or DCI format 0_1 DCI format 1_1) may include a field different from the fields described above.

In various aspects of the present embodiment, the number of resource blocks indicates the number of resource blocks in the frequency domain unless otherwise specified.

The downlink grant is used at least for scheduling a single PDSCH in a single serving cell.

The uplink grant is used at least for scheduling a single PUSCH in a single serving cell.

One physical channel may be mapped to one serving cell. A single physical channel may be mapped to a single BWP configured to a single carrier included in a single serving cell.

In the terminal apparatus 1, one or multiple COntrol REsource SETs (CORESETs) may be configured. The terminal apparatus 1 monitors the PDCCH in the one or multiple control resource sets. Here, monitoring of the PDCCH in the one or multiple control resource sets may include monitoring of one or multiple PDCCHs corresponding to the one or multiple control resource sets, respectively. Note that the PDCCH may include a set of one or multiple PDCCH candidates and/or one or multiple PDCCH candidates. Also, monitoring of the PDCCH may include monitoring and detecting the PDCCH and/or a DCI format transmitted via the PDCCH.

The control resource set may indicate a time-frequency domain to which one or multiple PDCCHs can be mapped. The control resource set may be an area in which the terminal apparatus 1 monitors the PDCCH. The control resource set may include continuous resources (Localized resources). The control resource set may include non-continuous resources (distributed resources).

In the frequency domain, the unit of mapping of the control resource set may be a resource block. In the frequency domain, for example, the unit of mapping of the control resource set may be six resource blocks. In the time domain, the unit of mapping of the control resource set may be an OFDM symbol. In the time domain, for example, the unit of mapping of the control resource set may be one OFDM symbol.

Mapping of the control resource set to the resource block may be provided based at least on the higher layer parameter. The higher layer parameter may include a bitmap for a Resource Block Group (RBG). The resource block group may be provided by six continuous resource blocks.

The number of OFDM symbols included in the control resource set may be provided based at least on the higher layer parameter.

A certain control resource set may be a Common control resource set. The common control resource set may be a control resource set configured commonly to multiple terminal apparatuses 1. The common control resource set may be provided at least based on some or all of the MIB, the first system information, the second system information, the common RRC signaling, and a cell ID. For example, the time resource and/or the frequency resource of the control resource set configured to monitor the PDCCH to be used for scheduling the first system information may be provided based at least on the MIB.

The control resource set configured by the MIB is also referred to as CORESET #0. CORESET #0 may be a control resource set of index #0.

A certain control resource set may be a Dedicated control resource set. The dedicated control resource set may be a control resource set configured to be used exclusively for the terminal apparatus 1. The dedicated control resource set may be provided based at least on some or all of the dedicated RRC signaling and values of C-RNTI. Multiple control resource sets may be configured for the terminal apparatus 1, and an index (control resource set index) may be provided for each of the control resource sets. One or more control channel elements (CCEs) may be configured in the control resource set, and an index (CCE index) may be provided for each of the CCEs.

A set of candidates of the PDCCH monitored by the terminal apparatus 1 may be defined from the perspective of a search space. In other words, the set of PDCCH candidates monitored by the terminal apparatus 1 may be given by a search space.

The search space may include one or multiple PDCCH candidates of one or multiple Aggregation levels. The aggregation level of the PDCCH candidates may indicate the number of CCEs constituting the PDCCH. The PDDCH candidate may be mapped to one or multiple CCEs.

The terminal apparatus 1 may monitor at least one or multiple search spaces in the slot in which DRX (Discontinuous reception) is not configured. The DRX may be provided based at least on a higher layer parameter. The terminal apparatus 1 may monitor at least one or multiple Search space sets in the slot in which DRX is not configured. Multiple search space sets may be configured for the terminal apparatus 1. An index (search space set index) may be provided for each of the search space sets.

The search space set may at least include one or multiple search spaces. An index (search space index) may be provided for each of the search spaces.

Each search space set may be associated at least with one control resource set. Each search space set may be included in one control resource set. For each of the search space sets, the index of the control resource set related to the search space set may be given.

For each of the search space sets, a monitoring periodicity of the search space set may be configured. The monitoring periodicity of the search space set may at least indicate the interval of the slot in which monitoring of the search space set is performed by the terminal apparatus 1. A higher layer parameter at least indicating the monitoring periodicity of the search space set may be given for each search space set.

For each of the search space sets, a Monitoring offset of the search space set may be configured. The monitoring offset of the search space set may at least indicate an offset from a reference index (for example, slot #0) of an index of a slot in which monitoring of the search space set is performed by the terminal apparatus 1. A higher layer parameter at least indicating the monitoring offset of the search space set may be given for each search space set.

For each of the search space sets, a Monitoring pattern of the search space set may be configured. The monitoring pattern of the search space set may indicate the first OFDM symbol for the search space set in which monitoring is performed. The monitoring pattern of the search space set may be given by a bitmap indicating the first OFDM symbol in one or multiple slots. A higher layer parameter at least indicating the monitoring pattern of the search space set may be given for each search space set.

A Monitoring occasion for the search space set may be given based at least on a part or all of the monitoring periodicity of the search space set, the monitoring offset of the search space set, the monitoring pattern of the search space set, and/or configuration of DRX.

FIG. 4 is a diagram illustrating an example of the monitoring occasion for the search space set according to an aspect of the present embodiment. In FIG. 4 , a search space set 91 and a search space set 92 are configured in a primary cell 301, a search space set 93 is configured in a secondary cell 302, and a search space set 94 is configured in a secondary cell 303.

In FIG. 4 , each block hatched with grid lines represents the search space set 91, each block hatched with lines rising diagonally up and to the right represents the search space set 92, each block hatched with lines rising diagonally up and to the left represents the search space set 93, and each block hatched with horizontal lines represents the search space set 94.

The monitoring periodicity of the search space set 91 is set to one slot, the monitoring offset of the search space set 91 is set to zero slots, and the monitoring pattern of the search space set 91 is set to [1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0]. In other words, the monitoring occasion for the search space set 91 is the first OFDM symbol (OFDM symbol #0) and the eighth OFDM symbol (OFDM symbol #7) in each of the slots.

The monitoring periodicity of the search space set 92 is set to two slots, the monitoring offset of the search space set 92 is set to zero slots, and the monitoring pattern of the search space set 92 is set to [1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]. In other words, the monitoring occasion for the search space set 92 is the first OFDM symbol (OFDM symbol #0) in each of the even-numbered slots.

The monitoring periodicity of the search space set 93 is set to two slots, the monitoring offset of the search space set 93 is set to zero slots, and the monitoring pattern of the search space set 93 is set to [0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0]. In other words, the monitoring occasion for the search space set 93 is the eighth OFDM symbol (OFDM symbol #7) in each of the even-numbered slots.

The monitoring periodicity of the search space set 94 is set to two slots, the monitoring offset of the search space set 94 is set to one slot, and the monitoring pattern of the search space set 94 is set to [1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]. In other words, the monitoring occasion for the search space set 94 is the first OFDM symbol (OFDM symbol #0) in each of the odd-numbered slots.

The physical resources of the search space include configuration units (Control Channel Elements (CCEs)) of a control channel. The CCE includes a prescribed number of Resource Element Groups (REGs). For example, the CCE may include six REGs. The REG may include one Physical Resource Block (PRB) during one OFDM symbol. In other words, the REG may include 12 Resource Elements (REs). The PRB is also simply referred to as a Resource Block (RB).

The PDSCH is used at least to transmit the transport block. The PDSCH may be used at least to transmit a random access message 2 (random access response). The PDSCH may be used at least to transmit system information including parameters used for initial access.

In FIG. 1 , in downlink radio communication, the following downlink physical signals are used. The downlink physical signals need not be used for transmitting information output from a higher layer, but are used by a physical layer.

-   -   Synchronization signal (SS)     -   DownLink DeModulation Reference Signal (DL DMRS)     -   Channel State Information-Reference Signal (CSI-RS)     -   DownLink Phase Tracking Reference Signal (DL PTRS)

The synchronization signal is used by the terminal apparatus 1 to establish synchronization with a downlink frequency domain and/or time domain. The synchronization signal includes a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS).

An SS block (SS/PBCH block) includes at least some or all of the PSS, the SSS, and the PBCH.

The DL DMRS is related to transmission of the PBCH, the PDCCH, and/or the PDSCH. The DL DMRS is multiplexed on the PBCH, the PDCCH, and/or the PDSCH. In order to channel compensation of the PBCH, the PDCCH, or the PDSCH, the terminal apparatus 1 may use the DL DMRS corresponding to the PBCH, the PDCCH, or the PDSCH.

The CSI-RS may be a signal used at least to calculate channel state information. A pattern of the CSI-RS assumed by the terminal apparatus may be provided at least by a higher layer parameter.

The PTRS may be a signal that is at least used for compensation of phase noise. A pattern of the PTRS assumed by the terminal apparatus may be provided based at least on a higher layer parameter and/or the DCI.

The DL PTRS may be related to the DL DMRS group at least including an antenna port used for one or multiple DL DMRSs.

The downlink physical channel and the downlink physical signal are also collectively referred to as the downlink signal. The uplink physical channel and the uplink physical signal are also collectively referred to as the uplink signal. The downlink signal and the uplink signal are also collectively referred to as the physical signal. The downlink signal and the uplink signal are also collectively referred to as the signal. The downlink physical channel and the uplink physical channel are collectively referred to as the physical channel. The downlink physical signal and the uplink physical signal are collectively referred to as the physical signal.

A Broadcast CHannel (BCH), an Uplink-Shared CHannel (UL-SCH), and a Downlink-Shared CHannel (DL-SCH) are transport channels. A channel used in a Medium Access Control (MAC) layer is referred to as a transport channel A unit of the transport channel used in the MAC layer is also referred to as a transport block (TB) or an MAC PDU. Control of the Hybrid Automatic Repeat reQuest (HARQ) is performed for each transport block in the MAC layer. The transport block is a unit of data that the MAC layer delivers to the physical layer. In the physical layer, the transport block is mapped to a codeword, and modulation processing is performed for each codeword.

The base station apparatus 3 and the terminal apparatus 1 exchange (transmit and/or receive) a higher layer signaling in a higher layer. For example, the base station apparatus 3 and the terminal apparatus 1 may transmit and/or receive, in a Radio Resource Control (RRC) layer, RRC signaling (a Radio Resource Control (RRC) message and/or Radio Resource Control (RRC) information). The base station apparatus 3 and the terminal apparatus 1 may transmit and/or receive an MAC Control Element (CE) in the MAC layer. Here, the RRC signaling and/or the MAC CE is also referred to as a higher layer signaling.

The PUSCH and the PDSCH may be at least used for transmitting the RRC signaling and/or the MAC CE. Here, the RRC signaling transmitted on the PDSCH from the base station apparatus 3 may be signaling that is common to multiple terminal apparatuses 1 in a serving cell. The signaling common to the multiple terminal apparatuses 1 in the serving cell is also referred to as common RRC signaling. The RRC signaling transmitted from the base station apparatus 3 through the PDSCH may be signaling dedicated to a certain terminal apparatus 1 (also referred to as dedicated signaling or UE specific signaling). The signaling dedicated to the terminal apparatus 1 is also referred to as dedicated RRC signaling. A serving cell-specific higher layer parameter may be transmitted using the signaling common to the multiple terminal apparatuses 1 in the serving cell or the signaling dedicated to a certain terminal apparatus 1. A UE-specific higher layer parameter may be transmitted using signaling dedicated to a certain terminal apparatus 1.

A Broadcast Control CHannel (BCCH), a Common Control CHannel (CCCH), and a Dedicated Control CHannel (DCCH) are logical channels. For example, the BCCH is a channel of a higher layer that is used for transmitting the MIB. The Common Control CHannel (CCCH) is a channel of a higher layer that is used for transmitting common information in multiple terminal apparatuses 1. Here, the CCCH may be, for example, used for the terminal apparatus 1 that is not in a state of RRC connection. The Dedicated Control CHannel (DCCH) is a channel of a higher layer that is at least used for transmitting control information (dedicated control information) that is dedicated to the terminal apparatus 1. Here, the DCCH may be, for example, used for the terminal apparatus 1 that is in a state of RRC connection.

The BCCH in the logical channel may be mapped to the BCH, the DL-SCH, or the UL-SCH in the transport channel. The CCCH in the logical channel may be mapped to the DL-SCH or the UL-SCH in the transport channel. The DCCH in the logical channel may be mapped to the DL-SCH or the UL-SCH in the transport channel.

The UL-SCH in the transport channel may be mapped to the PUSCH in the physical channel. The DL-SCH in the transport channel may be mapped to the PDSCH in the physical channel. The BCH in the transport channel may be mapped to the PBCH in the physical channel.

In the following, a configuration example of the terminal apparatus 1 according to an aspect of the present embodiment will be described.

FIG. 5 is a schematic block diagram illustrating a configuration of the terminal apparatus 1 according to an aspect of the present embodiment. As illustrated in the figure, the terminal apparatus 1 includes a radio transmission and/or reception unit 10 and a higher layer processing unit 14. The radio transmission and/or reception unit 10 at least includes a part or all of an antenna unit 11, a Radio Frequency (RF) unit 12, and a baseband unit 13. The higher layer processing unit 14 at least includes a part or all of a medium access control layer processing unit 15 and a radio resource control layer processing unit 16. The radio transmission and/or reception unit 10 may include at least a part or all of a transmitter and a receiver.

The higher layer processing unit 14 outputs uplink data (transport block) generated by a user operation or the like to the radio transmission and/or reception unit 10. The higher layer processing unit 14 performs processing of an MAC layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, and an RRC layer.

The medium access control layer processing unit 15 included in the higher layer processing unit 14 performs processing of the MAC layer.

The radio resource control layer processing unit 16 included in the higher layer processing unit 14 performs processing of the RRC layer. The radio resource control layer processing unit 16 performs management of various pieces of configuration information/parameters of its apparatus. The radio resource control layer processing unit 16 sets various pieces of configuration information/parameters, based on a higher layer signaling received from the base station apparatus 3. Specifically, the radio resource control layer processing unit 16 sets various pieces of configuration information/parameters, based on information indicating the various pieces of configuration information/parameters received from the base station apparatus 3. Note that the configuration information may include information related to the processing or configurations of the physical channel, the physical signal (that is, the physical layer), the MAC layer, the PDCP layer, the RLC layer, and the RRC layer. The parameters may be higher layer parameters.

The radio transmission and/or reception unit 10 performs processing of the physical layer, such as modulation, demodulation, coding, and decoding. The radio transmission and/or reception unit 10 separates, demodulates, and decodes a received physical signal, and outputs the decoded information to the higher layer processing unit 14. The radio transmission and/or reception unit 10 generates a physical signal by performing modulation and coding of data and generating a baseband signal (conversion into a time-continuous signal) and transmits the physical signal to the base station apparatus 3.

The RF unit 12 converts (down converts) a signal received via the antenna unit 11 into a baseband signal by orthogonal demodulation and removes unnecessary frequency components. The RF unit 12 outputs a processed analog signal to the baseband unit.

The baseband unit 13 converts the analog signal input from the RF unit 12 into a digital signal. The baseband unit 13 removes a portion corresponding to a Cyclic Prefix (CP) from the converted digital signal, performs a Fast Fourier Transform (FFT) on the signal from which the CP has been removed, and extracts a signal in the frequency domain.

The baseband unit 13 generates an OFDM symbol by performing Inverse Fast Fourier Transform (IFFT) on the data, adds CP to the generated OFDM symbol, generates a baseband digital signal, and converts the baseband digital signal into an analog signal. The baseband unit 13 outputs the converted analog signal to the RF unit 12.

The RF unit 12 removes unnecessary frequency components from the analog signal input from the baseband unit 13 through a low-pass filter, up converts the analog signal into a signal of a carrier frequency, and transmits the up converted signal via the antenna unit 11. The RF unit 12 amplifies power. The RF unit 12 may have a function of controlling transmission power. The RF unit 12 is also referred to as a transmission power control unit.

In the following, a configuration example of the base station apparatus 3 according to an aspect of the present embodiment will be described.

FIG. 6 is a schematic block diagram illustrating a configuration of the base station apparatus 3 according to an aspect of the present embodiment. As illustrated in the figure, the base station apparatus 3 includes a radio transmission and/or reception unit 30 and a higher layer processing unit 34. The radio transmission and/or reception unit 30 includes an antenna unit 31, an RF unit 32, and a baseband unit 33. The higher layer processing unit 34 includes a medium access control layer processing unit 35 and a radio resource control layer processing unit 36. The radio transmission and/or reception unit 30 may include at least a part or all of a transmitter and a receiver.

The higher layer processing unit 34 performs processing of an MAC layer, a PDCP layer, an RLC layer, and an RRC layer.

The medium access control layer processing unit 35 included in the higher layer processing unit 34 performs processing of the MAC layer.

The radio resource control layer processing unit 36 included in the higher layer processing unit 34 performs processing of the RRC layer. The radio resource control layer processing unit 36 generates, or acquires from a higher node, downlink data (transport block) mapped to a PDSCH, system information, an RRC message, an MAC CE, and the like, and outputs the data to the radio transmission and/or reception unit 30. The radio resource control layer processing unit 36 performs management of various pieces of configuration information/parameters of each of the terminal apparatuses 1. The radio resource control layer processing unit 36 may set various pieces of configuration information/parameters for each of the terminal apparatuses 1 through a higher layer signaling. Specifically, the radio resource control layer processing unit 36 transmits or broadcasts information indicating the various pieces of configuration information/parameters. Note that the configuration information may include information related to the processing or configurations of the physical channel, the physical signal (that is, the physical layer), the MAC layer, the PDCP layer, the RLC layer, and the RRC layer. The parameters may be higher layer parameters.

The functionality of the radio transmission and/or reception unit 30 is similar to the functionality of the radio transmission and/or reception unit 10, and description thereof will thus be omitted.

Each of the units denoted by the reference sign 10 to the reference sign 16 included in the terminal apparatus 1 may be configured as a circuit. Each of the units denoted by the reference sign 30 to the reference sign 36 included in the base station apparatus 3 may be configured as a circuit.

The terminal apparatus 1 may perform Carrier sense prior to transmission of a physical signal. Also, the base station apparatus 3 may perform carrier sense prior to transmission of a physical signal. The carrier sense may be to perform Energy detection on a Radio channel. Whether the physical signal can be transmitted may be provided based on the carrier sense performed prior to transmission of the physical signal. In a case that the amount of energy detected in carrier sense performed prior to transmission of a physical signal is greater than a prescribed threshold value, for example, the transmission of the physical channel may not be performed, or it may be determined that the transmission is not possible. Also, in a case that the amount of energy detected in the carrier sense performed prior to the transmission of the physical signal is smaller than the prescribed threshold value, the transmission of the physical channel may be performed, or it may be determined that the transmission is possible. Moreover, in a case that the amount of energy detected in the carrier sense performed prior to the transmission of the physical signal is equal to the prescribed threshold value, the transmission of the physical channel may be performed or may not be performed. In other words, in a case that the amount of energy detected in the carrier sense performed prior to the transmission of the physical signal is equal to the prescribed threshold value, it may be determined that the transmission is not possible, or it may be determined that the transmission is possible.

A procedure in which whether the transmission of the physical channel is possible based on the carrier sense is also referred to as Listen Before Talk (LBT). A situation in which the transmission of the physical signal is determined to be not possible as a result of the LBT is also referred to as a busy state or busy. For example, the busy state may be a state in which the amount of energy detected in the carrier sense is greater than the prescribed threshold value. In addition, the situation in which the transmission of the physical signal is determined to be possible as a result of the LBT is also referred to as an idle state or idle. For example, the idle state may be a state in which the amount of energy detected in the carrier sense is smaller than the prescribed threshold value.

In a certain component carrier, New Radio-Unlicensed (NR-U) may be applied. In a certain serving cell, NR-U may be applied. A fact that NR-U is applied in a certain component carrier (or a certain serving cell) may at least include a technique (framework, configuration) including a part or all of the following element A1 to element A6.

-   Element A1: In the certain component carrier (or the certain serving     cell), the second SS burst set is configured -   Element A2: The base station apparatus 3 transmits the second     SS/PBCH block in the certain component carrier (or the certain     serving cell) -   Element A3: The terminal apparatus 1 receives the second SS/PBCH     block in the certain component carrier (or the certain serving cell) -   Element A4: The base station apparatus 3 transmits the PDCCH in the     second Type 0 PDCCH common search space set in the certain component     carrier (or the certain serving cell) -   Element A5: The terminal apparatus 1 receives the PDCCH in the     second Type 0 PDCCH common search space set in the certain component     carrier (or the certain serving cell) -   Element A6: A higher layer parameter (for example, a field included     in the MIB) related to NR-U indicates a first value (for example, 1)

In a certain component carrier, New Radio-Unlicensed (NR-U) need not be applied. In a certain serving cell, NR-U need not be applied. A fact that NR-U is not applied in a certain component carrier (or a certain serving cell) may at least include a technique (framework, configuration) including a part or all of the following element B1 to element B6.

-   Element B1: In the certain component carrier (or the certain serving     cell), the first SS burst set is configured -   Element B2: The base station apparatus 3 transmits the first SS/PBCH     block in the certain component carrier (or the certain serving cell) -   Element B3: The terminal apparatus 1 receives the first SS/PBCH     block in the certain component carrier (or the certain serving cell) -   Element B4: The base station apparatus 3 transmits the PDCCH in the     first Type 0 PDCCH common search space set in the certain component     carrier (or the certain serving cell) -   Element B5: The terminal apparatus 1 receives the PDCCH in the first     Type 0 PDCCH common search space set in the certain component     carrier (or the certain serving cell) -   Element B6: A higher layer parameter (for example, a field included     in the MIB) related to NR-U indicates a value (for example, 0)     different from the first value

The certain component carrier may be configured in a licensed band. The certain serving cell may be configured in a licensed band. Here, a fact that the certain component carrier (or the certain serving cell) is configured in a licensed band may at least include a part or all of the following configuration 1 to configuration 3.

-   Configuration 1: A higher layer parameter indicating operation in a     licensed band for the certain component carrier (or the certain     serving cell) is given, or a higher layer parameter indicating     operation in an unlicensed band for the certain component carrier     (or the certain serving cell) is not given -   Configuration 2: The certain component carrier (or the certain     serving cell) is configured so as to operate in a licensed band, or     the certain component carrier (or the certain serving cell) is not     configured so as to operate in an unlicensed band -   Configuration 3: The certain component carrier (or the certain     serving cell) is included in a licensed band, or the certain     component carrier (or the certain serving cell) is not included in     an unlicensed band

The licensed band may be such a band that the radio station license is required for the terminal apparatus that operates (is expected to operate) in the licensed band. The licensed band may be a band in which only terminal apparatuses manufactured by an operator (business entity, business, organization, company) with radio station license are allowed to operate. The unlicensed band may be such a band that the channel access procedure prior to transmission of the physical signal is not required.

The unlicensed band may be such a band that the radio station license is not required for the terminal apparatus that operates (is expected to operate) in the unlicensed band. The unlicensed band may be such a band in which terminal apparatuses manufactured by a part or all of an operator with the radio station license and/or an operator without the radio station license are allowed to operate. The unlicensed band may be such a band that the channel access procedure prior to transmission of the physical signal is required.

Whether or not NR-U is applied to the certain component carrier (or the certain serving cell) may be determined based on whether or not at least the certain component carrier (or the certain serving cell) is configured for a band that can be operated in the unlicensed band (for example, a band that can be operated only in the unlicensed band). For example, a list of bands designed for NR or carrier aggregation of NR may be defined. For example, in a case that a certain band is included in a band in which one or multiple bands in the list can be operated in the unlicensed band (for example, a band that can be operated only in the unlicensed band), NR-U may be applied to the certain band. In a case that a certain band is not included in a band in which one or multiple bands in the list can be operated in the unlicensed band (for example, a band that can be operated only in the unlicensed band), NR-U need not be applied to the certain band, and normal NR (for example, NR of release 15, or NR other than NR-U of release 16) may be applied.

Whether or not NR-U is applied to the certain component carrier (or the certain serving cell) may be determined based on whether or not at least the component carrier (or the serving cell) is configured for a band in which NR-U can be operated (for example, a band that can be operated only in NR-U). For example, in a case that the list of bands designed for operation of NR or carrier aggregation of NR is defined, and one or multiple bands in the list is defined as a band in which NR-U can be operated (for example, a band in which only NR-U can be operated), NR-U is applied for a case that a band configured for the component carrier (or the serving cell) is one of the one or multiple bands, and for a case it is a band other than the one or multiple bands, NR-U is not applied, and normal NR (for example, NR of release 15, or NR other than NR-U of release 16) may be applied.

Whether or not NR-U is applied to the certain component carrier (or the certain serving cell) may be determined based on information included in the system information (for example, the Master Information Block (MIB, or the Physical Broadcast Channel (PBCH))). For example, in a case that the MIB includes information indicating whether or not NR-U is applied, and the information indicates application of NR-U, NR-U may be applied to the serving cell corresponding to the MIB. In contrast, in a case that the information does not indicate application of NR-U, NR-U need not be applied to the serving cell corresponding to the MIB, and normal NR may be applied. Alternatively, the information may indicate whether or not operation is possible in the unlicensed band.

The certain component carrier may be configured in the unlicensed band. The certain serving cell may be configured in the unlicensed band. Here, a fact that the certain component carrier (or the certain serving cell) is configured in the unlicensed band may at least include a part or all of the following configuration 4 to configuration 6.

-   Configuration 4: A higher layer parameter indicating operation in     the unlicensed band is given to the certain component carrier (or     the certain serving cell) -   Configuration 5: The certain component carrier (or the certain     serving cell) is configured so as to operate in the unlicensed band -   Configuration 6: The certain component carrier (or the certain     serving cell) is included in the unlicensed band

The following description will be given based on the assumption that NR-U is applied or NR-U is not applied to the component carrier. Note that “NR-U is applied to the component carrier” may mean “NR-U is applied to the serving cell”, and “NR-U is not applied to the component carrier” may mean “NR-U is not applied to the serving cell”.

For example, in a case that NR-U is not applied to a certain component carrier, the terminal apparatus 1 may receive the first SS/PBCH block. In a case that NR-U is not applied to a certain component carrier, the terminal apparatus 1 may receive the first PDCCH in a first type 0 PDCCH common search space set. In a case that NR-U is not applied in a certain component carrier, the base station apparatus 3 may transmit the first SS/PBCH block. In a case that NR-U is not applied to a certain component carrier, the base station apparatus 3 may transmit the first PDCCH in the first type 0 PDCCH common search space set. The first SS/PBCH block may be received in one of the SS/PBCH block candidates included in the first SS burst set. The first SS/PBCH block may be transmitted in one of the SS/PBCH block candidates included in the first SS burst set.

The terminal apparatus 1 may multiplex uplink control information (UCI) to the PUCCH and transmit the PUCCH. The terminal apparatus 1 may multiplex the UCI to the PUSCH and transmit the PUSCH. The UCI may include at least one of downlink Channel State Information (CSI), a Scheduling Request (SR) indicating a request for a PUSCH resource, and Hybrid Automatic Repeat request ACKnowledgement (HARQ-ACK) information for downlink data (a Transport block, a Medium Access Control Protocol Data Unit (MAC PDU), a Downlink-Shared Channel (DL-SCH), a Physical Downlink Shared Channel (PDSCH)).

HARQ control for one transport block (TB) may be referred to as an HARQ process. The HARQ control is capable of parallel operation for multiple transport blocks (TBs). Each HARQ process may be associated with an HARQ process identifier.

The terminal apparatus 1 may be associated with a PDSCH group identifier (PDSCH Group ID (PGI)) regarding each PDSCH. The PGI of a certain PDSCH may be indicated based at least on the DCI format used for scheduling of the PDSCH. For example, a field indicating the PGI (PGI field) may be included in the DCI format. For example, the PDSCH group may be a set of PDSCHs having the same PDSCH group identifier (PGI). The PDSCH group may be one PDSCH, or a set of one or more PDSCHs associated with the same PGI. The number of PDSCH groups configured for the terminal apparatus 1 is N_(group). N_(group) may be 1, may be 2, may be 3, may be 4, or may be an integer of 0 or greater except for the numbers given. The number of PDSCH groups that can be configured for the terminal apparatus 1 is N_(group, max). For example, for the terminal apparatus 1, the number of PDSCH groups corresponding to an integer value of N_(group, max) or less may be configured. It may be set based at least on N_(group) and/or an RRC parameter.

The PGI field is a general term for the first PGI field and the second PGI field. The terminal apparatus 1 may determine a PDSCH group associated with a certain PDSCH, based at least on the value of the PGI field included in the DCI field used for scheduling of the certain PDSCH.

For example, the second PGI field may be included in DCI format 1_1. For example, the number N_(PGI, second) of bits of the second PGI field may be 1 or 2. For example, the number N_(PGI, second) of bits of the second PGI field may be given by ceil(log 2(N_(group))) For example, the number N_(PGI, second) of bits of the second PGI field may be given by ceil(log 2(N_(group, max))). For example, the first PGI field need not be included in DCI format 1_0. For example, the first PGI field may be included in DCI format 1_0. For example, the number N_(PGI, first) of bits of the first PGI field may be 1 or 2. For example, the number N_(PGI, first) of bits of the first PGI field may be given by ceil(log 2(N_(group))). For example, the number N_(PGI, first) of bits of the first PGI field may be given by ceil(log 2(N_(group, max))).

For example, for the terminal apparatus 1, DCI format 1_0 not including the first PGI field may be configured, and DCI format 1_1 including the second PGI field may be configured. Here, the number N_(PGI, second) of bits of the second PGI field may be ceil(log 2(N_(group))). Here, the number N_(PGI, second) of bits of the second PGI field may be greater than ceil(log 2(N_(group))). Here, the number N_(PGI, second) of bits of the second PGI field may be ceil(log 2(N_(group, max))). Here, the PDSCH group of PDSCHs scheduled by DCI format 1_0 may be associated with the PDSCH group having the smallest index (for example, the PDSCH group having index 0) out of the PDSCH group configured for the terminal apparatus 1. Here, the PDSCH group of PDSCHs scheduled by DCI format 1_0 may be associated with the PDSCH group having the largest index (for example, the PDSCH group having index N_(group)−1) out of the PDSCH group configured for the terminal apparatus 1. Here, the PDSCH group of PDSCHs scheduled by DCI format 1_0 may be associated with a prescribed PDSCH group (for example, the PDSCH group fixed in advance by the descriptions in specifications or the like). Here, the PDSCH group of PDSCHs scheduled by DCI format 1_0 need not be associated with any of the N_(group) PDSCH groups. Here, the PDSCH group of PDSCHs scheduled by DCI format 1_1 may be associated with the PDSCH group identified based at least on the value of the second PGI field.

For example, for the terminal apparatus 1, DCI format 1_0 including the first PGI field may be configured, and DCI format 1_1 including the second PGI field may be configured. Here, the number N_(PGI, first) of bits of the first PGI field may be ceil(log 2(N_(group))). Here, the number N_(PGI, first) of bits of the first PGI field may be greater than ceil(log 2(N_(group))). Here, the number N_(PGI, first) of bits of the first PGI field may be ceil(log 2(N_(group, max))). Here, the number N_(PGI, second) of bits of the second PGI field may be ceil(log 2(N_(group))). Here, the number N_(PGI, second) of bits of the second PGI field may be greater than ceil(log 2(N_(group))). Here, the number N_(PGI, second) of bits of the second PGI field may be ceil(log 2(N_(group, max))). Here, the PDSCH group of PDSCHs scheduled by DCI format 1_0 may be associated with the PDSCH group identified based at least on the value of the first PGI field. Here, the PDSCH group of PDSCHs scheduled by DCI format 1_1 may be associated with the PDSCH group identified based at least on the value of the second PGI field.

A Requested PDSCH Group (RPG) may be a PDSCH group corresponding to the HARQ-ACK information transmitted (reported) via the following PUCCH or PUSCH. The RPG (requested PDSCH group) may include one PDSCH group, or may include multiple PDSCH groups. Indication of the RPG may be indicated in association with each PDSCH group in a format of a bitmap, based at least on the DCI format. The RPG may be indicated based at least on the RPGI field included in the DCI format. The terminal apparatus 1 may generate the HARQ-ACK codebook for the indicated RPG, and transmit (report) the HARQ-ACK codebook via the PUCCH or the PUSCH.

The RPGI field is a general term for the first RPGI field and the second RPGI field. The terminal apparatus 1 may determine the requested PDSCH group, based at least on the value of the RPGI field.

For example, the second RPGI field may be included in DCI format 1_1. For example, the first RPGI field need not be included in DCI format 1_0. For example, the first RPGI field may be included in DCI format 1_0. For example, the number N_(RPG, second) of bits of the second RPGI field may be equal to N_(group). For example, the number N_(RPG, second) of bits of the second RPGI field may be equal to N_(group, max).

For example, for the terminal apparatus 1, DCI format 1_0 not including the first RPGI field may be configured, and DCI format 1_1 including the second RPGI field may be configured. Here, the number of bits of the second RPGI field may be equal to N_(group). Here, the number of bits of the second RPGI field may be equal to N_(group, max). Here, in response to detection of DCI format 1_0, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs associated with the PDSCH group having the smallest index (for example, the PDSCH group having index 0) may be triggered. Here, in response to detection of DCI format 1_0, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs associated with the PDSCH group having the largest index (for example, the PDSCH group having index N_(group)−1) may be triggered. Here, in response to detection of DCI format 1_0, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs associated with a prescribed PDSCH group (for example, the PDSCH group fixed in advance by the descriptions in specifications or the like) may be triggered. Here, in response to detection of DCI format 1_0, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs not associated with any of the N_(group) PDSCH groups may be triggered. Here, in response to detection of DCI format 1_1, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs corresponding to any one of one or multiple PDSCH groups indicated based at least on the second RPGI field may be triggered.

For example, for the terminal apparatus 1, DCI format 1_0 including the first RPGI field may be configured, and DCI format 1_1 including the second RPGI field may be configured. Here, the number of bits of the first RPGI field may be equal to N_(group). Here, the number of bits of the first RPGI field may be equal to N_(group, max). Here, the number of bits of the second RPGI field may be equal to N_(group). Here, the number of bits of the second RPGI field may be equal to N_(group, max). Here, in response to detection of DCI format 1_0, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs corresponding to any one of one or multiple PDSCH groups indicated based at least on the first RPGI field may be triggered. Here, in response to detection of DCI format 1_1, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs corresponding to any one of one or multiple PDSCH groups indicated based at least on the second RPGI field may be triggered.

A New Feedback Indicator (NFI) field may be a DCI field indicating whether or not the HARQ-ACK information including the HARQ-ACK bit corresponding to the transport block of the PDSCH is correctly detected. The NFI field may be a field indicating whether or not the HARQ-ACK bit stored in a recording medium such as a memory is to be erased (flushed).

The NFI field is a general term for the first NFI field and the second NFI field.

For example, for the terminal apparatus 1, DCI format 1_0 not including the first NFI field may be configured, and DCI format 1_1 including the second NFI field may be configured. Here, the number N_(NFI, second) of bits of the second NFI field may be equal to N_(group). Here, the number N_(NFI, second) of bits of the second NFI field may be equal to N_(group, max). Here, in response to detection of DCI format 1_0, it may be assumed that the NFI of the PDSCH group having the smallest index (for example, the PDSCH group having index 0) is toggled. Here, in response to detection of DCI format 1_0, it may be assumed that the NFI of the PDSCH group having the largest index (for example, the PDSCH group having index N_(group)−1) is toggled. Here, in response to detection of DCI format 1_0, it may be assumed that the NFI of a prescribed PDSCH group (for example, the PDSCH group fixed in advance by the descriptions in specifications or the like) is toggled. Here, in response to detection of DCI format 1_0, it may be assumed that the NFI of N_(group) PDSCH groups is toggled. Here, in response to detection of DCI format 1_0, it need not be assumed that the NFI of N_(group) PDSCH groups is toggled. Here, in response to detection of DCI format 1_1, transmission of one or multiple pieces of HARQ-ACK information corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs corresponding to any one of one or multiple PDSCH groups indicated based at least on the second NFI field may be triggered. Here, each of the bits of the second NFI field included in DCI format 1_1 may correspond to one PDSCH group.

For example, for the terminal apparatus 1, DCI format 1_0 including the first NFI field may be configured, and DCI format 1_1 including the second NFI field may be configured. Here, the number N_(NFI, first) of bits of the first NFI field may be 1. Here, the number N_(NFI, second) of bits of the second NFI field may be equal to N_(group). Here, the number N_(NFI, second) of bits of the second NFI field may be equal to N_(group, max). Here, the first NFI field included in DCI format 1_0 may correspond to the PDSCH group having the smallest index (for example, the PDSCH group having index 0). Here, the first NFI field included in DCI format 1_0 may correspond to the PDSCH group having the largest index (for example, the PDSCH group having index N_(group)−1). Here, the first NFI field included in DCI format 1_0 may correspond to a prescribed PDSCH group (for example, the PDSCH group fixed in advance by the descriptions in specifications or the like). Here, the first NFI field included in DCI format 1_0 may correspond to the PDSCH group associated with the PDSCH scheduled by DCI format 1_0. Here, each of the bits of the second NFI field included in DCI format 1_1 may correspond to one PDSCH group.

For example, for the terminal apparatus 1, DCI format 1_0 including the first NFI field may be configured, and DCI format 1_1 including the second NFI field may be configured. Here, the number N_(NFI, first) of bits of the first NFI field may be equal to N_(group). Here, the number N_(NFI, first) of bits of the first NFI field may be equal to N_(group, max). Here, the number N_(NFI, second) of bits of the second NFI field may be equal to N_(group). Here, the number N_(NFI, second) of bits of the second NFI field may be equal to N_(group, max). Here, each of the bits of the first NFI field included in DCI format 1_0 may correspond to one PDSCH group. Here, each of the bits of the second NFI field included in DCI format 1_1 may correspond to one PDSCH group.

For example, after the HARQ-ACK bit corresponding to the transport block included in the PDSCH scheduled by the DCI format is transmitted, the terminal apparatus 1 may store a value of an NFI bit corresponding to each PDSCH group indicated by the DCI format. For example, in a case that the terminal apparatus 1 receives the DCI format, the terminal apparatus 1 may store the value of the NFI bit corresponding to each PDSCH group indicated by the DCI format. Here, for the PDSCH, the received NFI bit may refer to an NFI bit that is indicated by the NFI field included in the DCI format used for scheduling of the PDSCH. For the PDSCH, the stored NFI bit may refer to an NFI bit that has already been stored in the terminal apparatus 1 before being detected by the DCI format used for scheduling of the PDSCH. For each PDSCH group, the initial value of the value of the stored NFI bit may be set to 0 in advance. The terminal apparatus 1 may compare the value of the received NFI bit and the value of the stored NFI bit, and determine whether or not the NFI bit corresponding to the PDSCH group is toggled. In a case that the values of the received NFI bit and the stored NFI bit are different, the terminal apparatus 1 may determine that the NFI bit is toggled. The terminal apparatus 1 may determine that the HARQ-ACK information corresponding to the PDSCH group for which the NFI bit (that is, the received NFI bit) is toggled is detected in the base station apparatus 3 in comparison to a value of a previously received NFI bit (that is, the stored NFI bit) for the PDSCH group. For example, in a case that the base station apparatus 3 detects the HARQ-ACK information corresponding to the PDSCH group, the base station apparatus 3 may toggle the NFI bit corresponding to the PDSCH group. In a case that the values of the received NFI bit and the stored NFI bit are the same, it may be determined that the NFI bit is not toggled. The terminal apparatus 1 may determine that the HARQ-ACK information corresponding to the PDSCH group for which the NFI bit (that is, the received NFI bit) is not toggled is not detected in the base station apparatus 3 in comparison to a value of a previously received NFI bit (that is, the stored NFI bit) for the PDSCH group. For example, in a case that the base station apparatus 3 does not detect the HARQ-ACK information corresponding to the PDSCH group, the base station apparatus 3 need not toggle the NFI bit corresponding to the PDSCH group. Here, “to toggle” means to switch to a different value.

The received NFI may include one or multiple received NFI bits. Each entry of the received NFI may be a received NFI bit corresponding to each PDSCH group. The stored NFI may include one or multiple stored NFI bits. Each entry of the stored NFI may be a stored NFI bit corresponding to each PDSCH group.

In a case that the terminal apparatus 1 generates the HARQ-ACK codebook corresponding to a certain PDSCH group, and the NFI bit is toggled in comparison to a value of a previously received NFI bit (that is, the stored NFI bit) for the PDSCH group, the terminal apparatus 1 may delete (need not include) the HARQ-ACK information reported (HARQ-ACK information other than HARQ-ACK information not reported yet) from the HARQ-ACK codebook corresponding to the PDSCH group. In a case that there is a PDSCH that is detected and for which the HARQ-ACK information is not reported yet out of the PDSCH group, the terminal apparatus 1 need not delete (may include) the HARQ-ACK information corresponding to the PDSCH. In other words, the terminal apparatus 1 may multiplex the HARQ-ACK information corresponding to the PDSCH on the HARQ-ACK codebook described above. For one or more pieces of HARQ-ACK information corresponding to the PDSCH group for which the NFI bit is toggled, the terminal apparatus 1 may flush the HARQ-ACK information that is reported, and need not flush the HARQ-ACK information that is not reported. Here, “to flush” means to bring the HARQ-ACK information to the initial value (for example, a NACK). In a case that the terminal apparatus 1 receives the NFI being toggled and then transmits the HARQ-ACK codebook corresponding to the PDSCH group for the NFI bit, the terminal apparatus 1 generates the HARQ-ACK codebook by using the HARQ-ACK information not being flushed (HARQ-ACK information not being reported) and transmits the HARQ-ACK codebook. In a case that the terminal apparatus 1 receives the NFI not being toggled and then transmits the HARQ-ACK codebook corresponding to the PDSCH group for the NFI bit, the terminal apparatus 1 generates the HARQ-ACK codebook by using the HARQ-ACK information not being flushed (HARQ-ACK information being reported and HARQ-ACK information not being reported) and transmits the HARQ-ACK codebook.

The terminal apparatus 1 may determine the HARQ-ACK codebook, based at least on whether or not the NFI bit is toggled. The terminal apparatus 1 may determine the HARQ-ACK codebook corresponding to a certain PDSCH group, based at least on whether or not the stored NFI bit and the received NFI bit corresponding to the certain PDSCH group are toggled.

A value of K1 (information or a parameter indicated by the timing indication field from the PDSCH to the HARQ feedback) indicated by the DCI format included in the PDCCH may be a numerical value (numerical), or may be a non-numerical value (non-numerical). Here, the value of the numerical value may indicate a value expressed in numbers, and for example, may be a value out of {0, 1, 2, . . . , 15}. The value of the non-numerical value may indicate a value other than a number, or may indicate that a numerical value is not indicated. The use of the value of K1 being a numerical value and the value of K1 being a non-numerical value will be described below. For example, the PDSCH scheduled using the DCI format is transmitted in the base station apparatus 3 in slot n, and is received in the terminal apparatus 1. In a case that the value of K1 indicated by the DCI format is a numerical value, the terminal apparatus 1 may transmit (report) the HARQ-ACK information corresponding to the PDSCH in slot n+K1 via the PUCCH or the PUSCH. In a case that the value of K1 indicated by the DCI format is a non-numerical value, the terminal apparatus 1 may defer reporting of the HARQ-ACK information corresponding to the PDSCH. In a case that the value of K1 being a non-numerical value is indicated by the DCI format including scheduling information of the PDSCH, the terminal apparatus 1 may defer reporting of the HARQ-ACK information corresponding to the PDSCH. For example, the terminal apparatus 1 may store the HARQ-ACK information in a recording medium such as a memory, and transmit (report) the HARQ-ACK information with the transmission of the HARQ-ACK information being triggered based at least on a DCI format other than the DCI format described above, without transmitting (reporting) the HARQ-ACK information via the following PUCCH or PUSCH.

The value of K1 being a non-numerical value may be included in a first higher layer parameter sequence. The first higher layer parameter may be a higher layer parameter dl-DataToUL-ACK. The first higher layer parameter may be a higher layer parameter different from the higher layer parameter dl-DataToUL-ACK. The value of K1 may be a value indicated by the timing indication field from the PDSCH to the HARQ feedback included in DCI format 1_0 or DCI format 1_1 out of the first higher layer parameter sequence. For example, in a case that it is assumed that the first higher layer parameter sequence is set to {0, 1, 2, 3, 4, 5, 15, value of non-numerical value}, and the number of bits of the timing indication field from the PDSCH to the HARQ feedback is 3, the code point “000” of the timing indication field from the PDSCH to the HARQ feedback may indicate that the value of K1 is 0, the code point “001” may indicate that the value of K1 is 1, or the code point “111” may indicate that value of K1 is the value of the non-numerical value. For example, in a case that it is assumed that the first higher layer parameter sequence is set to {value of non-numerical value, 0, 1, 2, 3, 4, 5, 15}, and the number of bits of the timing indication field from the PDSCH to the HARQ feedback is 3, the code point “000” of the timing indication field from the PDSCH to the HARQ feedback may indicate that the value of K1 is the value of the non-numerical value, the code point “001” may indicate that the value of K1 is 0, and the code point “111” may indicate that the value of K1 is 15.

For example, the timing indication field from the PDSCH to the HARQ feedback included in DCI format 1_0 need not indicate the value of the non-numerical value. For example, a certain code point of the timing indication field from the PDSCH to the HARQ feedback included in DCI format 1_0 may indicate the value of the non-numerical value. For example, the timing indication field from the PDSCH to the HARQ feedback included in DCI format 1_1 need not indicate the value of the non-numerical value. For example, a certain code point of the timing indication field from the PDSCH to the HARQ feedback included in DCI format 1_1 may indicate the value of the non-numerical value.

FIG. 7 is a diagram illustrating a correspondence example between the monitoring occasion for the search space set (Monitoring occasion for search space set) and the monitoring occasion for the PDCCH (Monitoring occasion for PDCCH) according to an aspect of the present embodiment. In FIG. 7 , the monitoring occasion for the search space set in the primary cell is the first OFDM symbol of the slot, and the monitoring occasion for the search space set in the secondary cell is the first OFDM symbol of the slot and the intermediate OFDM symbol (for example, OFDM symbol #7) of the slot. In FIG. 7 , the monitoring occasion for the PDCCH corresponds to the first OFDM symbol of slot #n and the intermediate OFDM symbol of slot #n, and the first OFDM symbol of slot #n+1 and the intermediate OFDM symbol of slot #n+1. In other words, the monitoring occasion for the PDCCH may be defined as an occasion in which the monitoring occasion for the search space set is configured for at least one of one or multiple serving cells. The monitoring occasion for the PDCCH may correspond to an index of the OFDM symbol for which the monitoring occasion for the search space set is configured for at least one of one or multiple serving cells.

In the slot, the monitoring occasion for the search space set started from a certain OFDM symbol index may correspond to the monitoring occasion for the PDCCH started from the certain OFDM symbol index. The monitoring occasion for the PDCCH started from a certain OFDM symbol index may correspond to each monitoring occasion for the search space set started from the certain OFDM symbol index.

The terminal apparatus 1 may determine a set of monitoring occasions for the PDCCH for the HARQ-ACK information transmitted on the PUCCH mapped to the slot having index n (slot #n), based at least on some or all of a value of a timing K1 and a value of a slot offset K0. The set of monitoring occasions for the PDCCH for the HARQ-ACK information transmitted on the PUCCH mapped to the slot having index n is also referred to as a set of monitoring occasions for the PDCCH for the slot n (monitoring occasion for PDCCH for slot #n). Here, the set of monitoring occasions for the PDCCH includes M monitoring occasions for the PDCCH. For example, the slot offset K0 may be indicated based at least on a value of the time domain resource allocation field included in a downlink DCI format. The slot offset K0 is a value indicating the number of slots (difference of slots) from a slot including the last OFDM symbol to which the PDCCH including a DCI format including the time domain resource allocation field indicating the slot offset K0 is mapped to the first OFDM symbol of the PDSCH scheduled by the DCI format.

FIG. 8 is a diagram illustrating a configuration example of the set of monitoring occasions for the PDCCH for the slot n according to an aspect of the present embodiment. In FIG. 8 , the monitoring occasion for the search space set in the primary cell is the first OFDM symbol of a slot, and the monitoring occasion for the search space set in the secondary cell is the first OFDM symbol of a slot and the intermediate OFDM symbol (for example, OFDM symbol #7) of the slot. In FIG. 8 , the monitoring occasion for the search space set in the primary cell includes 801 and 804, and the monitoring occasion for the search space set in the secondary cell includes 802, 803, 805, and 806. In FIG. 8 , a DCI format 811 is detected in 802, a DCI format 812 is detected in 804, a DCI format 813 is detected in 805, and a DCI format 814 is detected in 806.

For example, in a case that transmission of the HARQ-ACK information in the slot n is indicated based at least on the timing K1 and the slot offset K0 indicated by the DCI format 811, the terminal apparatus 1 may determine the monitoring occasion for the PDCCH defined based at least on 801 as the PDCCH monitoring occasion for the slot n. For example, in a case that transmission of the HARQ-ACK information in the slot n is not indicated based at least on the timing K1 and the slot offset K0 indicated by the DCI format 812, and transmission of the HARQ-ACK information in the slot n is not indicated based at least on the timing K1 and the slot offset K0 indicated by the DCI format 813, the terminal apparatus 1 need not determine the monitoring occasion for the PDCCH defined based at least on some or all of 804 and 805 as the PDCCH monitoring occasion for the slot n. For example, in a case that transmission of the HARQ-ACK information in the slot n is indicated based at least on the timing K1 and the slot offset K0 indicated by the DCI format 814, the terminal apparatus 1 may determine the monitoring occasion for the PDCCH defined based at least on 806 as the PDCCH monitoring occasion for the slot n.

In other words, in a case that the DCI format detected in any one monitoring occasion for the search space set corresponding to a certain monitoring occasion for the PDCCH triggers transmission of the HARQ-ACK information in the slot n, the terminal apparatus 1 may determine the monitoring occasion for the PDCCH as the PDCCH monitoring occasion for the slot n. In a case that the DCI format detected in the monitoring occasion for the search space set corresponding to a certain monitoring occasion for the PDCCH does not trigger transmission of the HARQ-ACK information in the slot n, the terminal apparatus 1 need not determine the monitoring occasion for the PDCCH as the PDCCH monitoring occasion for the slot n. In a case that the DCI format is not detected in the monitoring occasion for the search space set corresponding to a certain monitoring occasion for the PDCCH, the terminal apparatus 1 need not determine the monitoring occasion for the PDCCH as the PDCCH monitoring occasion for the slot n.

The PUCCH resource used for transmission of the HARQ-ACK information in the slot n may be identified based at least on the PUCCH resource indication field that is included in the last DCI format among one or multiple DCI formats detected in the set of monitoring occasions for the PDCCH for the slot n. Here, each of the one or multiple DCI formats triggers transmission of the HARQ-ACK information in the slot n. The last DCI format may be a DCI format corresponding to the last index (largest index) among the DCI formats detected in the set of monitoring occasions for the PDCCH for the slot n. The index of the DCI format in the set of monitoring occasions for the PDCCH for the slot n is given in ascending order for the index of the serving cell in which the DCI format is detected, and is then given in ascending order for the index of the monitoring occasion for the PDCCH in which the DCI format is detected. The index of the monitoring occasion for the PDCCH is given in ascending order on the time axis.

A second higher layer parameter may include a higher layer parameter related to generation and reporting of the HARQ-ACK information. A first value in the second higher layer parameter may correspond to a conventional specification to which NR-U is not applied. A second value in the second higher layer parameter may correspond to a specification to which NR-U is applied. A higher layer parameter pdsch-HARQ-ACK-Codebook may be a higher layer parameter indicating a type of the HARQ-ACK codebook. The higher layer parameter pdsch-HARQ-ACK-Codebook may be given to any of semi-static and dynamic. The higher layer parameter pdsch-HARQ-ACK-Codebook may be given to the value of enhancedDynamic-r16. The value of enhancedDynamic-r16 in the higher layer parameter pdsch-HARQ-ACK-Codebook may correspond to application of NR-U. For the terminal apparatus 1, a part or all of the following configurations may be configured in a case that NR-U is applied. Here, the configuration of the higher layer parameter related to the HARQ-ACK codebook in a case that NR-U is applied may be referred to as NR-U HARQ-ACK configuration.

-   -   Configuration 1: The second higher layer parameter is given     -   Configuration 2: The second higher layer parameter is given to         the second value     -   Configuration 3: The higher layer parameter         pdsch-HARQ-ACK-Codebook is given to enhancedDynamic-r16

In a case that the higher layer parameter pdsch-HARQ-ACK-Codebook is given to the value of semi-static, for generation of the HARQ-ACK codebook, the size of the HARQ-ACK codebook may be semi-statically determined based at least on the higher layer parameter in advance. In other words, the size of the HARQ-ACK codebook may not depend on an actual detection state of the DCI format. In a case that the higher layer parameter pdsch-HARQ-ACK-Codebook is given to the value of dynamic, for generation of the HARQ-ACK codebook, the size of the HARQ-ACK codebook may be dynamically determined based at least on the counter DAI and/or the total DAI indicated by the detected DCI format. In a case that the higher layer parameter pdsch-HARQ-ACK-Codebook is given to the value of semi-static or dynamic, the terminal apparatus 1 may not expect more than one PDSCH group. In a case that the higher layer parameter pdsch-HARQ-ACK-Codebook is given to the value of enhancedDynamic-r16, the HARQ-ACK codebook or the sub-codebook may be generated for each PDSCH group. In a case that the higher layer parameter pdsch-HARQ-ACK-Codebook is given to the value of enhancedDynamic-r16, the terminal apparatus 1 may not expect one or more than one PDSCH group.

In a case that NR-U HARQ-ACK configuration is given, for the PDSCH group g associated with the scheduled PDSCH, the terminal apparatus 1 may include the monitoring occasion for the PDCCH corresponding to the DCI format at least satisfying a part or all of condition A1, condition A2, and condition A3 in the set of monitoring occasions for the PDCCH for the slot n. For the PDSCH group g, the base station apparatus 3 may expect that the HARQ-ACK information having triggered transmission corresponds to the monitoring occasion for the PDCCH after a time when the NFI bit corresponding to the PDSCH group g is finally toggled. In the terminal apparatus 1, the set of monitoring occasions for the PDCCH is determined based at least on the toggle state of the NFI bit indicated by the base station apparatus 3, so that ambiguity of recognition for a reception and/or transmission state of the HARQ-ACK information between the terminal apparatus 1 and the base station apparatus 3 is avoided. Therefore, efficient transmission and/or reception of the HARQ-ACK information can be implemented.

-   -   Condition A1: The HARQ-ACK information corresponding to the         PDSCH scheduled by the DCI format is triggered to be transmitted         via the PUCCH in the slot n     -   Condition A2: The PDSCH group g is indicated by the PGI field         included in the DCI format     -   Condition A3: The DCI format is detected after a time when an         event in which the NFI bit corresponding to the PDSCH group g is         toggled finally occurred

Here, the event in which the NFI bit is toggled refers to an event in which the received NFI is toggled in comparison to the stored NFI.

FIG. 9 is a diagram illustrating a configuration example of the set of monitoring occasions for the PDCCH for the slot n according to an aspect of the present embodiment. FIG. 10 is a diagram illustrating a configuration example of the set of monitoring occasions for the PDCCH for the slot n according to an aspect of the present embodiment.

In FIG. 9 and FIG. 10 , each of blocks hatched with diagonal lines represents a PDCCH, each of white blocks represents a PDSCH, and each of blocks hatched with vertical stripes represents a PUCCH. An arrow pointing to any one of the PUCCHs from each of the PDSCHs indicates that initial transmission of the HARQ-ACK bit corresponding to the transport block included in the PDSCH corresponding to the start point of the arrow is carried out in the PUCCH corresponding to the end point of the arrow. Here, a solid arrow indicates that transmission of the PUCCH is triggered by the DCI format used for scheduling of the PDSCH (the timing K1 is a numerical value), and a dotted arrow indicates that transmission of the PUCCH is not triggered by the DCI format used for scheduling of the PDSCH (the timing K1 is a non-numerical value). In FIG. 9 , the absence of the arrow pointing to the PUCCH from the PDSCH does not necessarily mean that transmission (initial transmission or the like) of the HARQ-ACK bit corresponding to the transport block included in the PDSCH is not triggered.

It is assumed that, in FIG. 9 and FIG. 10 , the terminal apparatus 1 is given the NR-U HARQ-ACK configuration.

In FIG. 9 , the DCI format used for scheduling of a PDSCH 911 is included in a PDCCH 901, the DCI format used for scheduling of a PDSCH 912 is included in a PDCCH 902, the DCI format used for scheduling of a PDSCH 913 is included in a PDCCH 903, the DCI format used for scheduling of a PDSCH 914 is included in a PDCCH 904, and the DCI format used for scheduling of a PDSCH 915 is included in a PDCCH 905.

In FIG. 9 , it is assumed that all of the PDSCHs are associated with the PDSCH group g. The terminal apparatus 1 transmits HARQ-ACK information 931 including the HARQ-ACK bit corresponding to the transport block included in the PDSCH 915 and the PDSCH 914 via a PUCCH 921 in the slot n. The terminal apparatus 1 may detect the PDCCH 901, and store the received NFI. In a case that the terminal apparatus 1 detects the PDCCH 902, the received NFI is indicated by the DCI format included in the PDCCH 902. By comparing the received NFI (having a value of 1) to the stored NFI (having a value of 0), the terminal apparatus 1 may determine that the NFI bit is toggled. After the determination, the terminal apparatus 1 may store the received NFI as the stored NFI. In a case that the terminal apparatus 1 detects the PDCCH 903, the received NFI is indicated by the DCI format included in the PDCCH 903. By comparing the received NFI (having a value of 0) to the stored NFI (having a value of 1), the terminal apparatus 1 may determine that the NFI bit is toggled. After the determination, the terminal apparatus 1 may store the received NFI as the stored NFI. In a case that the terminal apparatus 1 detects the PDCCH 904, the received NFI is indicated by the DCI format included in the PDCCH 904. By comparing the received NFI (having a value of 1) to the stored NFI (having a value of 0), the terminal apparatus 1 may determine that the NFI bit is toggled. After the determination, the terminal apparatus 1 may store the received NFI as the stored NFI. In a case that the terminal apparatus 1 detects the PDCCH 905, the received NFI is indicated by the DCI format included in the PDCCH 905. By comparing the received NFI (having a value of 1) to the stored NFI (having a value of 1), the terminal apparatus 1 may determine that the NFI bit is not toggled. After the determination, the terminal apparatus 1 may store the received NFI as the stored NFI. An event in which the NFI bit is toggled at a time when the PDCCH 904 is detected is the last NFI bit toggle event before the PUCCH 921 is transmitted. For generation of the HARQ-ACK ACK information 931, the terminal apparatus 1 may include the monitoring occasions for the PDCCH corresponding to the DCI format from the last NFI bit toggle event until detection of the last DCI format in the set of monitoring occasions for the PDCCH for the slot n. For example, the terminal apparatus 1 may include the monitoring occasions for the PDCCH corresponding to the PDCCH 904 and the PDCCH 905 in the set of monitoring occasions for the PDCCH for the slot n. The NFI bit toggle event is an event in which it is determined that the NFI bit is toggled. The NFI bit toggle event is triggered by the NFI bit included in the DCI format. In a case that the NFI bit (received NFI) included in the DCI format is toggled in comparison to the stored NFI, the NFI bit toggle event is triggered.

In other words, in a case that the NR-U HARQ-ACK configuration is given, for the PDSCH group g associated with the scheduled PDSCH, the terminal apparatus 1 may determine the set of monitoring occasions for the PDCCH for the slot n, based at least on determination (specification, identification, recognition, judgment) of the last NFI bit toggle event. For example, for the PDSCH group g, the terminal apparatus 1 may include the monitoring occasions for the PDCCH at or after the timing of occurrence of the last NFI bit toggle event in the set of monitoring occasions for the PDCCH for the slot n. For example, for the PDSCH group g, the terminal apparatus 1 may include the monitoring occasion for the PDCCH at the timing of occurrence of the last NFI bit toggle event in the set of monitoring occasions for the PDCCH for the slot n. For example, for the PDSCH group g, the terminal apparatus 1 need not include the monitoring occasions for the PDCCH at or before the timing of occurrence of the last NFI bit toggle event in the set of monitoring occasions for the PDCCH for the slot n.

Further, for example, for the PDSCH group g, the terminal apparatus 1 may include the monitoring occasions for the PDCCH at or after the monitoring occasion for the PDCCH in which the DCI format related to the last NFI bit toggle event is detected in the set of monitoring occasions for the PDCCH for the slot n. For example, for the PDSCH group g, the terminal apparatus 1 may include the monitoring occasion for the PDCCH in which the DCI format related to the last NFI bit toggle event is detected in the set of monitoring occasions for the PDCCH for the slot n. For example, for the PDSCH group g, the terminal apparatus 1 need not include the monitoring occasions for the PDCCH at or before the monitoring occasion for the PDCCH in which the DCI format related to the last NFI bit toggle event is detected in the set of monitoring occasions for the PDCCH for the slot n. Here, the DCI format related to the last NFI bit toggle event is a DCI format that triggers occurrence of the last NFI bit toggle event.

In a case that the NR-U HARQ-ACK configuration is given, the terminal apparatus 1 may store the HARQ-ACK report state for reception of the PDSCH. The initial value of the HARQ-ACK report state may be set to N/A, null, or undefined in advance. After receiving the PDSCH, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to reception of the PDSCH to unreported. In a case that transmission of the HARQ-ACK bit corresponding to reception of the PDSCH is triggered in a certain uplink physical channel, the terminal apparatus 1 may set the HARQ-ACK report state to reported. In a case that the terminal apparatus 1 detects that, for PDSCH reception with the HARQ-ACK report state being reported, the NFI bit corresponding to the PDSCH group associated with the PDSCH is toggled in comparison to a previously received NFI bit, the terminal apparatus 1 may delete the HARQ-ACK report state (or set to the initial value). In a case that the terminal apparatus 1 detects that, for PDSCH reception with the HARQ-ACK report state being unreported, the NFI bit corresponding to the PDSCH group associated with the PDSCH is toggled in comparison to a previously received NFI bit, the terminal apparatus 1 need not delete the HARQ-ACK report state (or set to the initial value). In other words, the terminal apparatus 1 may maintain the HARQ-ACK report state as unreported. For the PDSCH group g associated with the scheduled PDSCH, the terminal apparatus 1 may include the monitoring occasion for the PDCCH corresponding to the DCI format satisfying a part or all of condition A1, condition A2, and condition B1 in the set of monitoring occasions for the PDCCH for the slot n. For the PDSCH group g, the base station apparatus 3 may expect that the HARQ-ACK information having triggered transmission corresponds to the monitoring occasion for the PDCCH in which the NFI corresponding to the PDSCH group g is not toggled (in the terminal apparatus 1, the HARQ-ACK report state has the initial value). In the terminal apparatus 1, the set of monitoring occasions for the PDCCH is determined based at least on the toggle state of the NFI bit indicated by the base station apparatus 3, so that ambiguity of recognition for a reception and/or transmission state of the HARQ-ACK information between the terminal apparatus 1 and the base station apparatus 3 is avoided. Therefore, efficient transmission and/or reception of the HARQ-ACK information can be implemented.

-   -   Condition B1: The HARQ-ACK report state corresponding to         reception of the PDSCH scheduled by the DCI format is unreported         or reported

For the PDSCH group g associated with the scheduled PDSCH, the terminal apparatus 1 need not include the monitoring occasion for the PDCCH corresponding to the DCI format at least not satisfying at least one of condition A1, condition A2, or condition B1 in the set of monitoring occasions for the PDCCH for the slot n.

In FIG. 9 , in a case that the PDCCH 901 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 911 to unreported. After transmitting the HARQ-ACK information corresponding to the PDSCH 911, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 911 to reported. In a case that the PDCCH 902 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 911 to the initial value in response to the NFI bit being toggled. In a case that the PDCCH 902 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 912 to unreported. In a case that the PDCCH 903 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 912 to the initial value in response to the NFI bit being toggled. In a case that the PDCCH 903 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 913 to unreported. In a case that the PDCCH 904 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 913 to the initial value in response to the NFI bit being toggled. In a case that the PDCCH 904 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 914 to unreported. In a case that the PDCCH 905 is detected, the terminal apparatus 1 may maintain the HARQ-ACK report state corresponding to the PDSCH 914 as reported in response to the NFI bit being not toggled. In a case that the PDCCH 905 is detected, the terminal apparatus 1 may set the HARQ-ACK report state corresponding to the PDSCH 915 to unreported. Before the PUCCH 921 is transmitted, the HARQ-ACK report state corresponding to the PDSCH 911, the PDSCH 912, and the PDSCH 913 has the initial value, the HARQ-ACK report state corresponding to the PDSCH 914 is reported, and the HARQ-ACK report state corresponding to the PDSCH 915 is unreported. For generation of the HARQ-ACK information 931, the terminal apparatus 1 may include the monitoring occasion for the PDCCH corresponding to the PDSCH with the HARQ-ACK report state being unreported or reported in the set of monitoring occasions for the PDCCH for the slot n. For example, the terminal apparatus 1 may include the monitoring occasion for the PDCCH corresponding to the PDSCH 914 and the PDSCH 915 in the set of monitoring occasions for the PDCCH for the slot n. For example, the terminal apparatus 1 need not include the monitoring occasion for the PDCCH corresponding to the PDSCH 911, the PDSCH 912, and the PDSCH 913 in the set of monitoring occasions for the PDCCH for the slot n.

FIG. 11 is a diagram illustrating an example related to indication of the counter DAI and the total DAI according to an aspect of the present embodiment.

In the M monitoring occasions for the PDCCH (set of monitoring occasions for the PDCCH for the slot n), for a certain monitoring occasion for the PDCCH in a certain serving cell, a Counter DAI indicates a cumulative number (or may be a value at least related to the cumulative number) of the PDCCHs detected before the monitoring occasion for the PDCCH in the serving cell. The counter DAI may also be referred to as a C-DAI. The total DAI may indicate a cumulative number of the PDCCHs detected before a certain monitoring occasion for the PDCCH (or may be a value at least related to the cumulative number) in the M monitoring occasions for the PDCCH. The total DAI may be referred to as a Total Downlink Assignment Index (T-DAI).

The DAI field is a general term for the first DAI field and the second DAI field. “Other group DAI field” is a general term for the first other group DAI field and the second other group DAI field. Such other group DAI field used for generation of the HARQ-ACK codebook for a certain PDSCH may be included in the DCI format used for scheduling of a PDSCH group different from the PDSCH group associated with the PDSCH. For example, such other group DAI field may be such other group DAI field included in the DCI format.

For example, in a case that one serving cell is configured and the higher layer parameter pdsch-HARQ-ACK-Codebook is given to the value of dynamic, the number of bits of the second DAI field may be 2, and the second DAI field may indicate the counter DAI. In other words, 2 bits of the second DAI field may be the counter DAI. In a case that more than one serving cell is configured, and the higher layer parameter pdsch-HARQ-ACK-Codebook is given to the value of dynamic, the number of bits of the second DAI field is 4, the Most Important Bit (MSB) of the 2 bits of the second DAI field may indicate the counter DAI, and the Least Significant Bit (LSB) of the 2 bits of the second DAI field may indicate the total DAI. In other words, the MSB of the 2 bits of the second DAI field may be the counter DAI. In other words, the LSB of the 2 bits of the second DAI field may be the total DAI.

The total DAI used for generation of the HARQ-ACK codebook for a certain PDSCH may be indicated by the bits of a part or all of the second DAI field included in the DCI format used for scheduling of a PDSCH group different from the PDSCH group associated with the PDSCH. For example, the total DAI may be indicated by the MSB of 1 bit, or the MSB of 2 bits, or the MSB of 3 bits in the second DAI field. For example, the total DAI may be indicated by the LSB of 1 bit, or the LSB of 2 bits, or the LSB of 3 bits in the second DAI field.

The following will describe indication of the counter DAI and the total DAI. In FIG. 11 , the arrow pointing to any one of the counter DAI (C-DAI) and the total DAI (T-DAI) from each of the DAI field (DAI field) and such other group DAI field (OG-DAI field) indicates indication of the counter DAI or the total DAI by the DAI field or such other group DAI field. The number of bits of such other group DAI field may be 1 (in other words, may be configured to 1). The number of bits of such other group DAI field may be 2 (in other words, may be configured to 2). The number of bits of such other group DAI field may be configured to 3 (in other words, may be configured to 3). The number of bits of such other group DAI field may be the number of bits used for indication of the counter DAI (in other words, may be configured for the number of bits used for indication of the counter DAI). The number of bits of such other group DAI field may be given by the higher layer parameter.

In FIG. 11 , the counter DAI may be indicated by the first DAI field or the second DAI field. The total DAI may be indicated by such other group DAI field. In a case that the number of bits of the second DAI field is 2, the counter DAI may be indicated by the second DAI field. In a case that the number of bits of the second DAI field is 4, the counter DAI may be indicated by the Most Important Bit (MSB) of the 2 bits of the second DAI field. In a case that the number of bits of the second DAI field is 4, the total DAI may be indicated by the Least Significant Bit (LSB) of the 2 bits of the second DAI field. For example, in a case that one serving cell is configured, and the NR-U HARQ-ACK configuration is not given, the counter DAI may be indicated by the first DAI field or the second DAI field. For example, in a case that one serving cell is configured, and the NR-U HARQ-ACK configuration is not given, the total DAI may not be indicated. For example, in a case that one serving cell is configured, and the NR-U HARQ-ACK configuration is given, and multiple PDSCH groups are scheduled, the total DAI may be indicated by such other group DAI field.

In FIG. 10 and FIG. 11 , indication of the total DAI by such other group DAI field in the HARQ-ACK codebook for the PDSCH 1011 in retransmission via a PUCCH 1022 will be described. Here, the PDSCH 1011 scheduled by a PDCCH 1001 is associated with the PDSCH group g, a PDSCH 1012 scheduled by the a PDCCH 1002 and a PDSCH 1013 scheduled by a PDCCH 1003 are associated with a PDSCH group h different from the PDSCH group g. The following will describe generation of the HARQ-ACK information for the PDSCH group g. The terminal apparatus 1 receives the PDCCH 1001 including the DCI format for scheduling the PDSCH 1011, and transmits HARQ-ACK information 1031 including the HARQ-ACK bit corresponding to the PDSCH 1011 via a PUCCH 1021. Here, it is assumed that the PUCCH 1021 is not detected in the base station apparatus 3, and retransmission of the HARQ-ACK information 1031 is performed via the PUCCH 1022. Such other group DAI field for the PDSCH 1011 associated with the PDSCH group g may be included in the DCI format included in the PDCCH 1002 and/or the PDCCH 1003 associated with the PDSCH group h. The counter DAI used for generation of the HARQ-ACK codebook for the PDSCH 1011 may be indicated by the DAI field included in the PDCCH 1001. The total DAI used for generation of the HARQ-ACK codebook for the PDSCH 1011 may be indicated by the DAI field included in the PDCCH 1001. The total DAI used for generation of the HARQ-ACK codebook for the PDSCH 1011 may be indicated by such other group DAI field.

FIG. 12 , FIG. 13 , and FIG. 14 are diagrams illustrating an example of a procedure of configuration of a HARQ-ACK codebook (codebook of HARQ-ACK information) according to an aspect of the present embodiment. <AX> of FIG. 12 , FIG. 13 , and FIG. 14 is also referred to as step AX. In FIG. 12 , FIG. 13 , and FIG. 14 , “A=B” may mean that A is set to B. In FIG. 12 , FIG. 13 , and FIG. 14 , “A=B” may mean that B is input to A. The terminal apparatus 1 generates the HARQ-ACK codebook, based on the procedure illustrated in FIG. 12 , FIG. 13 , and FIG. 14 . In a case that the NR-U HARQ-ACK configuration is given, the terminal apparatus 1 may generate the HARQ-ACK codebook, based on the procedure illustrated in FIG. 12 , FIG. 13 , and FIG. 14 for each PDSCH group, and in a case that multiple HARQ-ACK codebooks are generated, the terminal apparatus 1 may connect the multiple HARQ-ACK codebooks.

The HARQ-ACK codebook may be given based at least on some or all of step A1 to step A58.

The HARQ-ACK codebook corresponding to a certain PDSCH group may be given based at least on some or all of step A1 to step A46. The HARQ-ACK codebook corresponding to a certain PDSCH group may be given based on one or multiple HARQ-ACK bits corresponding to any one of one or multiple transport blocks included in any one of one or multiple PDSCHs included in the certain PDSCH group.

The HARQ-ACK codebook may be given based at least on some or all of a set of monitoring occasions for the PDCCH, a value of a UL DAI field and/or a DAI field, and/or other group DAI field.

The HARQ-ACK codebook may be given based at least on some or all of a set of monitoring occasions for the PDCCH, a UL DAI, a counter DAI, and/or a total DAI.

In step A1, a serving cell index c is set to 0. The serving cell index may be given based at least on a higher layer parameter for each serving cell.

In step A2, m=0 is set. m may indicate an index of the monitoring occasion for the PDCCH including DCI format 1_0 or DCI format 1_1.

In step A3, j may be set to 0.

In step A4, V_(temp) may be set to 0.

In step A5, V_(temp2) may be set to 0.

In step A6, V_(s)=φ may be set. φ indicates an empty set.

In step A7, N^(DL) _(cells) may be set to the number of serving cells. The number of serving cells may be the number of serving cells configured for the terminal apparatus 1.

In step A8, M may be set to the number of monitoring occasions for the PDCCH.

In step A9, the first evaluation expression m<M is evaluated. In a case that the first evaluation expression is true, step A10 may be performed. In a case that the first evaluation expression is false, step A34 may be performed.

In step A10, c may be set to 0.

In step A11, the second evaluation expression c<N^(DL) _(cells) is evaluated. In a case that the second evaluation expression is true, step A11 may be performed. In a case that the second evaluation expression is false, step A33 may be performed.

In step A12, in a case that a monitoring occasion m for the PDCCH in a serving cell c is before switching of an activated downlink BWP, step A13 may be performed. In step A12, in a case that there is switching of an activated uplink BWP in the PCell, and switching of the activated downlink BWP is not triggered by DCI format 1_1, step A13 may be performed. In a case that neither of the two conditions described above is satisfied, step A14 may be performed.

In step A13, c may be set to c+1.

In step A14, step A15 may be performed.

In step A15, in a case that the NR-U HARQ-ACK configuration is not given, and condition C1 or condition C2 is satisfied, step A16 may be executed. In a case that the NR-U HARQ-ACK configuration is given, and condition C3 or condition C4 is satisfied in step A15, step A16 may be executed.

-   Condition C1: There is a PDSCH related to the PDCCH in the     monitoring occasion m for the PDCCH in the serving cell c -   Condition C2: There is a PDCCH indicating release of the SPS PDSCH     in the serving cell c -   Condition C3: There is a PDSCH that is associated with the PDSCH     group g and related to the PDCCH in the monitoring occasion m for     the PDCCH in the serving cell c -   Condition C4: There is a PDCCH indicating release of the SPS PDSCH     in the serving cell c and associated with the PDSCH group g

In step A16, the third evaluation expression V^(DL) _(C-DAI, c, m)≤V_(temp) is evaluated. In a case that the third evaluation expression is true, step A17 may be performed. In a case that the third evaluation expression is false, step A18 may be performed.

V^(DL) _(C-DAI, c, m) is a value of a counter Downlink Assignment Index (DAI) given based at least on the PDCCH detected in the monitoring occasion m for the PDCCH in the serving cell c. In determination of the counter DAI, for the index of the PDCCH detected in the M monitoring occasions, the serving cell index c may be given first and the monitoring occasion m for the PDCCH may be given second. In other words, the index of the PDCCH detected in the M monitoring occasions for the PDCCH is first mapped in order of the serving cell index c, and may then be mapped in order of the monitoring occasion m for the PDCCH (serving cell index first, PDCCH monitoring occasion second mapping). The counter DAI may be referred to as a Counter Downlink Assignment Index (C-DAI).

In step A17, j may be set to j+1.

Step A18 may be a step indicating completion of operation based on the third evaluation expression in step A12.

In step A19, V_(temp) may be set to V^(DL) _(C-DAI, c, m).

In step A20, the fourth evaluation expression V^(DL) _(T-DAI, m)=φ may be evaluated. In a case that the fourth evaluation expression is true, step A21 may be performed. In a case that the fourth evaluation expression is false, step A22 may be performed.

V^(DL) _(T-DAI, m) may be a value of the total DAI given based at least on the PDCCH detected in the monitoring occasion m for the PDCCH in the serving cell c. The total DAI may indicate a cumulative number of the PDCCHs detected before the monitoring occasion m for the PDCCH (or may be a value at least related to the cumulative number) in the M monitoring occasions for the PDCCH. The total DAI may be referred to as a Total Downlink Assignment Index (T-DAI).

The HARQ-ACK codebook may be multiplexed on the PUSCH scheduled based at least on DCI format 0_1, and V^(DL) _(T-DAI, m) may be replaced by V^(UL) _(DAI) at least in a case that m=M−1.

In step A21, V_(temp2) may be set to V^(DL) _(C-DAI, c, m).

In step A22, step A23 may be performed.

In step A23, V_(temp2) may be set to V^(DL) _(T-DAI, m).

Step A24 may be a step indicating completion of operation based on the fourth evaluation expression in step A20.

In step A25, in a case that 1) harq-ACK-SpatialBundlingPUCCH is not provided, 2) the monitoring occasion m for the PDCCH is a monitoring occasion for the PDCCH including DCI format 1_0 or DCI format 1_1, 3) maxNrofCodeWordsScheduledByDCI is configured in at least one BWP in at least one serving cell for reception of two transport blocks, step A26 may be performed. maxNrofCodeWordsScheduledByDCI may be information indicating whether or not transmission of two transport blocks on PDSCH is supported.

In step A26, o^(ACK) _(a)(8j+2 (V^(DL) _(C-DAI, c, m)−1)) may be set to a value of the HARQ-ACK bit corresponding to the first transport block of the serving cell c. In a case that the value of the HARQ-ACK bit is 1, this may indicate an ACK. In a case that the value of the HARQ-ACK bit is 0, this may indicate a NACK. The first transport block of the serving cell c may be the first transport block included in the PDSCH scheduled using a DCI format that is included in the PDCCH detected in the monitoring occasion m for the PDCCH in the serving cell c. o^(ACK) _(a)(X) is o^(−ACK) _(X).

In step A27, o^(ACK) _(a)(8j+2 (V^(DL) _(C-DAI, c, m)−1)+1) may be set to a value of the HARQ-ACK bit corresponding to the second transport block of the serving cell c. The second transport block of the serving cell c may be the second transport block included in the PDSCH scheduled using a DCI format that is included in the PDCCH detected in the monitoring occasion m for the PDCCH in the serving cell c.

In a case that the PDSCH includes the first transport block, and the PDSCH does not include the second transport block, this may indicate that one transport block is included in the PDSCH.

In step A28, V_(s) may be set to V_(s)∪{8j+2 (V^(DL) _(C-DAI, c, m)−1), 8j+2 (V^(DL) _(C-DAI, c, m)−1)+1}. Y∪Z may indicate a union of set Y and set Z. {*} may be a set including *.

In step A29, in a case that 1) harq-ACK-SpatialBundlingPUCCH is provided, 2) the monitoring occasion m for the PDCCH is a monitoring occasion for the PDCCH including DCI format 1_1, and 3) maxNrofCodeWordsScheduledByDCI is configured in at least one BWP in at least one serving cell for reception of two transport blocks, step A30 may be performed.

In step A30, o^(ACK) _(a)(4j+V^(DL) _(C-DAI, c, m)−1) may be set to a value given by a logical product (binary AND operation) of the first HARQ-ACK bit corresponding to the first transport block of the serving cell c and the second HARQ-ACK bit corresponding to the second transport block of the serving cell c.

In step A31, V_(s) may be set to V_(s)∪{4j+V^(DL) _(C-DAI, c, m)−1}.

In step A32, in a case that the condition of step A25 and the condition of step A29 are not satisfied, step A33 may be performed.

In step A33, o^(ACK) _(a)(4j+V^(DL) _(C-DAI, c, m)−1) may be set to a value of the first HARQ-ACK bit corresponding to the first transport block of the serving cell c. In step A33, o^(ACK) _(a)(4j+V^(DL) _(C-DAI, c, m)−1) may be set to a value of the HARQ-ACK bit of the serving cell c.

In step A34, V_(s) may be set to V_(s)∪{4j+V^(DL) _(C-DAI, c, m)−1}.

Step A35 may be a step indicating completion of operation of step A25.

Step A36 may be a step indicating completion of operation of step A15.

In step A37, c may be set to c+1.

Step A38 may be a step indicating completion of operation of step A12.

In step A39, step A11 may be performed.

In step A40, m may be set to m+1.

In step A41, step A10 may be performed.

In step A42, the fifth evaluation expression V_(temp2)<V_(temp) may be performed. In a case that the fifth evaluation expression is true, step A43 may be performed. In a case that the fifth evaluation expression is false, step A44 may be performed.

In step A43, j may be set to j+1.

Step A44 may be a step indicating completion of step A42.

In step A45, in a case that 1) harq-ACK-SpatialBundlingPUCCH is not provided, and 2) maxNrofCodeWordsScheduledByDCI is configured in at least one BWP in at least one serving cell, step A46 may be performed. In a case that neither of the two conditions described above is satisfied, step A47 may be performed.

In step A46, O^(ACK) may be set to 2 (4j+V_(temp2)).

In step A47, step A48 may be performed.

In step A48, O^(ACK) may be set to 4j+V_(temp2).

Step A49 may be a step indicating completion of operation of step A12.

In step A50, o^(ACK) _(a)(i_(N)) may be set to a value of a NACK for i_(N) that satisfies i_(N)∈{0, 1, . . . , O^(ACK)−1}¥ V_(s). V ¥ W may indicate a set obtained by eliminating elements included in set W from set V. V ¥ W may be a set difference of V regarding W.

In step A51, c may be set to 0.

In step A52, the seventh evaluation expression c<N^(DL) _(cell) is evaluated. In a case that the seventh evaluation expression is true, step A54 may be performed. In a case that the second evaluation expression is false, step A58 may be performed.

In step A54, in a case that a PDSCH (SPS PDSCH) scheduled using a configured grant in one or multiple slots in the M monitoring occasions for the PDCCH is configured to be received, and transmission of the SPS PDSCH is activated, step A54 may be performed.

In step A54, O^(ACK) may be set to O^(ACK)+1. In step A54, O^(ACK) may be set to O^(ACK)+N_(SPS). N_(SPS) may be the number of SPS PDSCHs configured to be received in M monitoring occasions 1001 for the PDCCH.

In step A55, o^(ACK)(O^(ACK)−1) may be set to a value of the HARQ-ACK bit corresponding to the transport block included in the SPS PDSCH. In step A55, o^(ACK)(O^(ACK)−i_(SPS)) may be set to a value of the HARQ-ACK bit corresponding to the transport block included in the SPS PDSCH. i_(SPS) may satisfy the condition of i_(SPS)∈{0, 1, . . . , N_(SPS)−1}. In step A55, o^(ACK)(O^(ACK)−1) may be set to a value given by a logical product of the HARQ-ACK bits corresponding to the transport blocks included in each of one or multiple SPS PDSCHs configured to be received in M monitoring occasions for the PDCCH.

Step A56 may be a step indicating completion of operation of step A53.

In step A57, c may be set to c+1.

Step A58 may be a step indicating completion of operation of step A52.

The first evaluation expression to the seventh evaluation expression are each also referred to as an evaluation expression. In a case that an evaluation expression is true, this may indicate that the evaluation expression is satisfied. In a case that the evaluation expression is false, this may indicate that the evaluation expression is not true. In a case that the evaluation expression is false, this may indicate that the evaluation expression is not satisfied.

O^(ACK) is the size of the HARQ-ACK codebook (for example, the number of bits included in the HARQ-ACK codebook). O^(ACK) may correspond to each PDSCH group. O_(ACK) is the number of bits of the UCI corresponding to the HARQ-ACK information multiplexed on the PUCCH or the PUSCH. O_(ACK) may be given by O^(ACK).

The terminal apparatus 1 may generate the HARQ-ACK codebook corresponding to the PDSCH, based at least on the counter DAI indicated by the DAI field included in the DCI format used for scheduling of the PDSCH and the total DAI indicated by the DCI payload (for example, such other group DAI field) included in a DCI format other than the DCI format. The DCI payload may be the DCI field. The DCI payload may be a part of the bits included in one certain DCI field. For example, the DCI payload may be a part or all of such other group DAI field. For example, the DCI payload may be a part or all of the DAI field. Here, the number of bits of the DAI field is assumed as X. X may be an integer of 2 or greater. The number of bits of the DCI payload (for example, such other group DAI field) may be an integer of 1 or greater and X−1 or less. For example, in a case that X is 2, Y may be 1. For example, in a case that X is 3, Y may be 2. For example, in a case that X is 3, Y may be 1. The terminal apparatus 1 may be determined the size of coarse granularity of the HARQ-ACK codebook, based at least on the total DAI indicated by the DCI payload (for example, such other group DAI field).

FIG. 15 is a diagram illustrating a method of indicating the total DAI by the DCI payload according to an aspect of the present embodiment.

In FIG. 15 , a Compressed indication method for the total DAI will be described. The compressed indication method is a method of indicating the total DAI by the DCI payload (for example, such other group DAI field) of the number of bits less than the number of bits of the DAI field used for indication of the counter DAI.

In FIG. 15 , in a case that the total DAI is indicated by the DCI payload (for example, such other group DAI field) of X bits, the value of any one total DAI of {1, 2, . . . , pow(2, X)} may be indicated by the DCI payload. Such an indication method may be referred to as an indication method of the original total DAI (Original T-DAI). Here, in the indication method of the original total DAI, the initial value of the value of the total DAI is 1, granularity is 1, and the value of the total DAI is not compressed. In the first compressed indication method, the value of any one total DAI of {G, 2G, . . . , pow(2, X)} may be indicated by the DCI payload of Y bits smaller than X. Here, G may be pow(2, X)/pow(2, Y), and may be the granularity of the value and the initial value of the total DAI obtained by compressed indication. As an example of the first compressed indication, in a case that X is 2, and Y is 1, the value of the original total DAI may be 1, 2, 3, and 4, and the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be 2, 2, 4, and 4. As an example of the second compressed indication, for example, in a case that X is 3, and Y is 2, the value of the original total DAI may be 1, 2, 3, 4, 5, 6, 7, and 8, and the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be 2, 2, 4, 4, 6, 6, 8, and 8. Here, in the example of the first compressed indication and the example of the second compressed indication, the granularity of the value and the initial value of the total DAI obtained by compressed indication are 2. For example, in a case that X is 3, and Y is 1, the value of the original total DAI may be 1, 2, 3, 4, 5, 6, 7, and 8, and the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be 4, 4, 4, 4, 8, 8, 8, and 8. Here, the granularity of the value and the initial value of the total DAI obtained by compressed indication are 4.

In FIG. 15 , in the second compressed indication method, whether the total DAI is an odd number or an even number may be indicated by the DCI payload (for example, such other group DAI field) of 1 bit. For example, in a case that the DCI payload of 1 bit indicates value 0, an odd-numbered total DAI may be indicated. In a case that the DCI payload of 1 bit indicates value 1, an even-numbered total DAI may be indicated. For example, in a case that the DCI payload of 1 bit indicates value 0, an even-numbered total DAI may be indicated. In a case that the DCI payload of 1 bit indicates value 1, an odd-numbered total DAI may be indicated. For example, in a case that X is 2, the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be given to an odd number, an even number, an odd number, and even number. For example, in a case that X is 3, the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be given to an odd number, an even number, an odd number, an even number, an odd number, an even number, an odd number, and an even number.

In FIG. 15 , in the third compressed indication method, in a case that X is 2, and Y is 1, the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be 3, 3, 3, and 4. In the fourth compressed indication method, in a case that X is 2, and Y is 1, the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be 1, 4, 4, and 4. In the fifth compressed indication method, in a case that X is 3, and Y is 2, the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be pow(2, 0), pow(2,1), pow(2, 2), pow(2, 2), pow(2, 3), pow(2, 3), pow(2, 3), and pow(2, 3). In the sixth compressed indication method, in a case that X is 3, and Y is 2, the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be 3, 3, 3, 5, 5, 7, 7, and 8. In the seventh compressed indication method, in a case that X is 3, and Y is 2, the value of the total DAI obtained by compressed indication and corresponding to the value of the original total DAI may be 1, 3, 3, 5, 5, 8, 8, and 8.

FIG. 16 is a diagram illustrating an example of switching of the DCI field used for indication of the total DAI according to an aspect of the present embodiment.

In FIG. 16 , in a case that the NR-U HARQ-ACK configuration is not given, and one serving cell is configured, the number of bits of information used for indication of the total DAI of the DAI field may be 0. In other words, the total DAI may not be indicated. In a case that the NR-U HARQ-ACK ACK configuration is not given, and multiple serving cells are configured, the number of bits of information used for indication of the total DAI of the DAI field may be 2. For example, the total DAI may be indicated by the LSB of 2 bits of the DAI field of 4 bits. For example, the total DAI may be indicated by the LSB of 3 bits of the DAI field of 6 bits. In a case that the NR-U HARQ-ACK configuration is given, the total DAI may be indicated by such other group DAI field. The number of bits of such other group DAI field may be 1, 2, or 3.

For example, in a case that the NR-U HARQ-ACK configuration is given, and one serving cell is configured, the number of bits of information used for indication of the total DAI of the DAI field may be 0. Further, in a case that the NR-U HARQ-ACK configuration is given, and multiple serving cells are configured, the number of bits of information used for indication of the total DAI of the DAI field may be 2.

For example, in a case that the NR-U HARQ-ACK configuration is given, the number of bits of information used for indication of the total DAI of such other group DAI field may be a prescribed value regardless of the number of serving cells configured. The prescribed value may be 1, 2, or 3.

According to an aspect of the present invention, efficient communication can be implemented. According to an aspect of the present invention, efficient transmission and/or reception of the HARQ-ACK information can be implemented. According to an aspect of the present invention, efficient transmission and/or reception of the HARQ-ACK codebook can be implemented.

Various aspects of apparatuses according to an aspect of the present embodiment will be described below.

(1) In order to accomplish the object described above, the present invention is contrived to provide the following measures. Specifically, a first aspect of the present invention is a terminal apparatus including: a receiver configured to receive a DCI format used for scheduling of a PDSCH; and a transmitter configured to transmit HARQ-ACK information corresponding to the PDSCH, wherein a HARQ-ACK codebook is generated based at least on a first total DAI indicated by the DCI format and a second total DAI different from the first total DAI, the number of bits of a DCI field indicating the first total DAI is X, X is an integer of 2 or greater, the number of bits of the DCI field indicating the second total DAI is Y, Y is an integer of 1 or greater and X−1 or less, and the HARQ-ACK codebook is included in the HARQ-ACK information.

(2) A second aspect of the present invention is the terminal apparatus, wherein the first total DAI indicates a total number of pairs of a serving cell and a PDCCH monitoring occasion, a size of the HARQ-ACK codebook is determined based at least on the first total DAI, the second total DAI is indicated by a DCI payload having the first total DAI being compressed as compared to a required DCI payload, and a size of coarse granularity of the HARQ-ACK codebook is determined based at least on the second total DAI.

(3) A third aspect of the present invention is a terminal apparatus for communicating with a base station apparatus by using one or multiple serving cells, the terminal apparatus including: a receiver configured to receive a DCI format used for scheduling of a PDSCH; and a transmitter configured to transmit HARQ-ACK information corresponding to the PDSCH, wherein a HARQ-ACK codebook is generated based at least on a total DAI, in a case that a higher layer parameter related to the HARQ-ACK codebook indicates a first value, the number of bits of the total DAI is 0 bits or 2 bits, based on whether or not the multiple serving cells are configured for the terminal apparatus, in a case that the higher layer parameter related to the HARQ-ACK codebook indicates a second value, the total DAI is 1, 2, or 3 bits, and the HARQ-ACK codebook is included in the HARQ-ACK information.

(4) A fourth aspect of the present invention is a terminal apparatus including: a receiver configured to receive a DCI format used for scheduling of a PDSCH; and a transmitter configured to transmit HARQ-ACK information corresponding to the PDSCH, wherein a HARQ-ACK codebook is generated based at least on a total DAI, the number of bits of a DCI field indicating the total DAI is configured by a higher layer parameter, and the HARQ-ACK codebook is included in the HARQ-ACK information.

(5) A fifth aspect of the present invention is a base station apparatus including: a transmitter configured to transmit a DCI format used for scheduling of a PDSCH; and a receiver configured to receive HARQ-ACK information corresponding to the PDSCH, wherein a HARQ-ACK codebook is generated based at least on a first total DAI indicated by the DCI format and a second total DAI different from the first total DAI, the number of bits of a DCI field indicating the first total DAI is X, X is an integer of 2 or greater, the number of bits of the DCI field indicating the second total DAI is Y, Y is an integer of 1 or greater and X−1 or less, and the HARQ-ACK codebook is included in the HARQ-ACK information.

(6) A sixth aspect of the present invention is the base station apparatus, wherein the first total DAI indicates a total number of pairs of a serving cell and a PDCCH monitoring occasion, a size of the HARQ-ACK codebook is determined based at least on the first total DAI, the second total DAI is indicated by a DCI payload having the first total DAI being compressed as compared to a required DCI payload, and a size of coarse granularity of the HARQ-ACK codebook is determined based at least on the second total DAI.

(7) A seventh aspect of the present invention is a base station apparatus for communicating with a terminal apparatus by using one or multiple serving cells, the base station apparatus including: a transmitter configured to transmit a DCI format used for scheduling of a PDSCH; and a receiver configured to receive HARQ-ACK information corresponding to the PDSCH, wherein a HARQ-ACK codebook is generated based at least on a total DAI, in a case that a higher layer parameter related to the HARQ-ACK codebook indicates a first value, the number of bits of the total DAI is 0 bits or 2 bits, based on whether or not the multiple serving cells are configured for the terminal apparatus, in a case that the higher layer parameter related to the HARQ-ACK codebook indicates a second value, the total DAI is 1, 2, or 3 bits, and the HARQ-ACK codebook is included in the HARQ-ACK information.

(8) An eighth aspect of the present invention is a base station apparatus including: a transmitter configured to transmit a DCI format used for scheduling of a PDSCH; and a receiver configured to receive HARQ-ACK information corresponding to the PDSCH, wherein a HARQ-ACK codebook is generated based at least on a total DAI, the number of bits of a DCI field indicating the total DAI is configured by a higher layer parameter, and the HARQ-ACK codebook is included in the HARQ-ACK information.

According to the above-described embodiment related to the present invention, transmission and/or reception of the HARQ-ACK information between the terminal apparatus 1 and the base station apparatus 3 can be appropriately implemented.

A program running on the base station apparatus 3 and the terminal apparatus 1 according to the present invention may be a program (program that causes a computer to function) that controls a Central Processing Unit (CPU) and the like, such that the program realizes the functions of the above-described embodiment according to one aspect of the present invention. Also, the information handled in these apparatuses is temporarily loaded into a Random Access Memory (RAM) while being processed, is then stored in a Hard Disk Drive (HDD) and various types of Read Only Memory (ROM) such as a Flash ROM, and is read, modified, and written by the CPU, as necessary.

Note that the terminal apparatus 1 and the base station apparatus 3 according to the aforementioned embodiment may be partially implemented by a computer. In such a case, a program for implementing such control functions may be recorded on a computer-readable recording medium to cause a computer system to read and execute the program recorded on this recording medium.

Note that it is assumed that the “computer system” mentioned here refers to a computer system built into the terminal apparatus 1 or the base station apparatus 3, and the computer system includes an OS and hardware components such as a peripheral device. Furthermore, a “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, and the like, and a storage device such as a hard disk built into the computer system.

Moreover, the “computer-readable recording medium” may include a medium that dynamically retains the program for a short period of time, such as a communication wire that is used to transmit the program over a network such as the Internet or over a communication line such as a telephone line, and a medium that retains the program for a certain period of time, such as a volatile memory within the computer system which functions as a server or a client in a case that the program is transmitted via the communication wire. Furthermore, the aforementioned program may be configured to implement part of the functions described above, and also may be configured to be capable of implementing the functions described above in combination with a program already recorded in the computer system.

The terminal apparatus 1 may include at least one processor, and at least one memory including a computer program instruction (computer program). The memory and the computer program instruction (computer program) may adopt a configuration of causing the terminal apparatus 1 to perform the operation and the processing described in the above embodiment by using a processor. The base station apparatus 3 may include at least one processor, and at least one memory including a computer program instruction (computer program). The memory and the computer program instruction (computer program) may adopt a configuration of causing the base station apparatus 3 to perform the operation and the processing described in the above embodiment by using a processor.

Furthermore, the base station apparatus 3 according to the aforementioned embodiment may be achieved as an aggregation (apparatus group) including multiple apparatuses. Each of the apparatuses included in such an apparatus group may include each function, or some or all portions of each functional block of the base station apparatus 3 according to the aforementioned embodiment. As the apparatus group, it is only necessary to have a complete set of functions or functional blocks of the base station apparatus 3. Moreover, the terminal apparatus 1 according to the aforementioned embodiment can also communicate with the base station apparatus as the aggregation.

Also, the base station apparatus 3 according to the aforementioned embodiment may be an Evolved Universal Terrestrial Radio Access Network (EUTRAN) and/or a NextGen RAN (NG-RAN or NR RAN). Moreover, the base station apparatus 3 according to the aforementioned embodiment may have some or all of the functions of a higher node for an eNodeB and/or a gNB.

Also, some or all portions of each of the terminal apparatus 1 and the base station apparatus 3 according to the aforementioned embodiment may be implemented as an LSI which is a typical integrated circuit or may be implemented as a chip set. The functional blocks of each of the terminal apparatus 1 and the base station apparatus 3 may be individually implemented as a chip, or some or all of the functional blocks may be integrated into a chip. A circuit integration technique is not limited to the LSI, and may be implemented with a dedicated circuit or a general-purpose processor. Moreover, in a case that with advances in semiconductor technology, a circuit integration technology with which an LSI is replaced appears, it is also possible to use an integrated circuit based on the technology.

In addition, although the aforementioned embodiments have described the terminal apparatus as an example of a communication apparatus, the present invention is not limited to such a terminal apparatus, and is applicable to a terminal apparatus or a communication apparatus that is a stationary type or a non-movable type electronic apparatus installed indoors or outdoors, for example, such as an AV device, a kitchen device, a cleaning or washing machine, an air-conditioning device, office equipment, a vending machine, and other household appliances.

Although, the embodiments of the present invention have been described in detail above referring to the drawings, the specific configuration is not limited to the embodiments and includes, for example, design changes within the scope not depart from the gist of the present invention. Furthermore, various modifications are possible within the scope of one aspect of the present invention defined by claims, and embodiments that are made by suitably combining technical means disclosed according to the different embodiments are also included in the technical scope of the present invention. Furthermore, a configuration in which elements described in the respective embodiments and having mutually the same effects, are substituted for one another is also included.

INDUSTRIAL APPLICABILITY

An aspect of the present invention can be utilized, for example, in a communication system, communication equipment (for example, a cellular phone apparatus, a base station apparatus, a wireless LAN apparatus, or a sensor device), an integrated circuit (for example, a communication chip), or a program.

REFERENCE SIGNS LIST

-   1 (1A, 1B, 1C) Terminal apparatus -   3 Base station apparatus -   10, 30 Radio transmission and/or reception unit -   11, 31 Antenna unit -   12, 32 RF unit -   13, 33 Baseband unit -   14, 34 Higher layer processing unit -   15, 35 Medium access control layer processing unit -   16, 36 Radio resource control layer processing unit -   91, 92, 93, 94 Search space set -   301 Primary cell -   302, 303 Secondary cell -   801, 802, 803, 804, 805, 806 Monitoring occasion for search space     set -   811, 812, 813, 814 DCI format -   1101, 1102, 1103, 1104, 1105 PDCCH -   1111, 1112, 1113, 1114, 1115 PDSCH -   1121, 1122, 1123 PUCCH 

The invention claimed is:
 1. A terminal apparatus comprising: a receiver configured to receive a Downlink Control Information (DCI) format and a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI format; and a transmitter configured to transmit Hybrid Automatic Repeat request ACKnowledgement (HARQ-ACK) information, wherein a first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format, the HARQ-ACK information is generated based at least on a Total Downlink Assignment Index (T-DAI) for a second PDSCH group different from the first PDSCH group, and in a case that a higher layer parameter pdsch-HARQ-ACK-Codebook is given to a value of enhancedDynamic-r16, a bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of a number of serving cells configured.
 2. A base station apparatus comprising: a transmitter configured to transmit a Downlink Control Information (DCI) format and a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI format; and a receiver configured to receive Hybrid Automatic Repeat request ACKnowledgement (HARQ-ACK) information, wherein a first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format, the HARQ-ACK information is generated based at least on a Total Downlink Assignment Index (T-DAI) for a second PDSCH group different from the first PDSCH group, and in a case that a higher layer parameter pdsch-HARQ-ACK-Codebook is given to a value of enhancedDynamic-r16, a bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of a number of serving cells configured.
 3. A communication method for a terminal apparatus, the communication method comprising the steps of: receiving a Downlink Control Information (DCI) format and a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI format; and transmitting Hybrid Automatic Repeat request ACKnowledgement (HARQ-ACK) information, wherein a first PDSCH group of the scheduled PDSCH is indicated by a PDSCH group index field in the DCI format, the HARQ-ACK information is generated based at least on a Total Downlink Assignment Index (T-DAI) for a second PDSCH group different from the first PDSCH group, and in a case that a higher layer parameter pdsch-HARQ-ACK-Codebook is given to a value of enhancedDynamic-r16, a bitwidth of information bits in the DCI format indicating the T-DAI is 2 regardless of a number of serving cells configured. 